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network (BGP and multiprotocol BGP)
redistribute (BGP to ISO IS-IS)
redistribute (ISO IS-IS to BGP)
neighbor timers
To set the timers for a specific BGP peer or peer group, use the neighbor timers command in address family or router configuration mode. To clear the timers for a specific BGP peer or peer group, use the no form of this command.
neighbor [ip-address | peer-group-name] timers keepalive holdtime [min-holdtime]
no neighbor [ip-address | peer-group-name] timers
Syntax Description
Defaults
keepalive: 60 seconds
holdtime: 180 secondsCommand Modes
Address family configuration (config-router-af)
Router configuration (config-router)Command History
Usage Guidelines
The timers configured for a specific neighbor or peer group override the timers configured for all BGP neighbors using the timers bgp command.
When configuring the holdtime argument for a value of less than twenty seconds, the following warning is displayed:
% Warning: A hold time of less than 20 seconds increases the chances of peer flappingIf the minimum acceptable hold-time interval is greater than the specified hold-time, a notification is displayed:
% Minimum acceptable hold time should be less than or equal to the configured hold time
Note
When the minimum acceptable hold-time is configured on a BGP router, a remote BGP peer session is established only if the remote peer is advertising a hold-time that is equal to, or greater than, the minimum acceptable hold-time interval. If the minimum acceptable hold-time interval is greater than the configured hold-time, the next time the remote session tries to establish, it will fail and the local router will send a notification stating "unacceptable hold time."
Examples
The following example changes the keepalive timer to 70 seconds and the hold-time timer to 210 seconds for the BGP peer 192.168.47.0:
router bgp 109 neighbor 192.168.47.0 timers 70 210The following example changes the keepalive timer to 70 seconds, the hold-time timer to 130 seconds, and the minimum hold-time interval to 100 seconds for the BGP peer 192.168.1.2:
router bgp 45000neighbor 192.168.1.2 timers 70 130 100neighbor transport
To enable a TCP transport session option for a Border Gateway Protocol (BGP) session, use the neighbor transport command in router or address family configuration mode. To disable a TCP transport session option for a BGP session, use the no form of this command.
neighbor {ip-address | peer-group-name} transport {connection-mode {active | passive} | path-mtu-discovery [disable] | multi-session | single-session}
no neighbor {ip-address | peer-group-name} transport {connection-mode | path-mtu-discovery | multi-session | single-session}
Syntax Description
Command Default
If this command is not configured, TCP path MTU discovery is enabled by default, but no other TCP transport session options are enabled.
Command Modes
Router configuration (config-router)
Address family configuration (config-router-af)Command History
Usage Guidelines
This command is used to specify various transport options. An active or passive transport connection can be specified for a BGP session. TCP transport path MTU discovery can be enabled to allow a BGP session to take advantage of larger MTU links. Use the show ip bgp neighbors command to determine whether TCP path MTU discovery is enabled.
In Cisco IOS Release 12.2(33)SRB and later releases, options can be specified for the transport of address family traffic using a single TCP session or to enable a separate TCP session for each address family. Multiple TCP sessions are used to support Multi-Topology Routing (MTR), and the single session option is available for backwards compatibility for non-MTR configurations and for scalability purposes.
In Cisco IOS Release 12.2(33)SRB and later releases, the ability to disable TCP path MTU discovery, for a single neighbor or for an inheriting peer or peer group, was added. If you use the disable keyword to disable discovery, discovery is also disabled on any peer or peer group that inherits the template in which you disabled discovery.
The following example shows how to configure the TCP transport connection to be active for a single internal BGP (iBGP) neighbor:
router bgp 45000neighbor 172.16.1.2 remote-as 45000neighbor 172.16.1.2 activateneighbor 172.16.1.2 transport connection-mode activeendThe following example shows how to configure the TCP transport connection to be passive for a single external BGP (eBGP) neighbor:
router bgp 45000neighbor 192.168.1.2 remote-as 40000neighbor 192.168.1.2 activateneighbor 192.168.1.2 transport connection-mode passiveendThe following example shows how to disable TCP path MTU discovery for a single BGP neighbor:
router bgp 45000neighbor 172.16.1.2 remote-as 45000neighbor 172.16.1.2 activateno neighbor 172.16.1.2 transport path-mtu-discoveryendThe following example shows how to reenable TCP path MTU discovery for a single BGP neighbor, if TCP path MTU discovery is disabled:
router bgp 45000neighbor 172.16.1.2 remote-as 45000neighbor 172.16.1.2 activateneighbor 172.16.1.2 transport path-mtu-discoveryendThe following example shows how to enable a separate TCP session for each address family for an MTR topology configuration:
router bgp 45000scope globalneighbor 172.16.1.2 remote-as 45000neighbor 172.16.1.2 transport multi-sessionaddress-family ipv4topology VIDEObgp tid 100neighbor 172.16.1.2 activateendThe following example shows how to disable TCP path MTU discovery and verify that it is disabled:
router bgp 100bgp log-neighbor-changestimers bgp 0 0redistribute staticneighbor 10.4.4.4 remote-as 100neighbor 10.4.4.4 update-source Loopback 0!endRouter# show ip bgp neighbors 10.4.4.4 | include pathUsed as bestpath: n/a 0Used as multipath: n/a 0Transport(tcp) path-mtu-discovery is enabledOption Flags: nagle, path mtu capableRouter#Router# configure terminalRouter(config)# router bgp 100Router(config-router)# neighbors 10.4.4.4 transport path-mtu-discovery disableRouter(config-router)# endRouter# show ip bgp neighbor 10.4.4.4 | include pathUsed as bestpath: n/a 0Used as multipath: n/a 0Transport(tcp) path-mtu-discovery is disabledRelated Commands
neighbor ttl-security
To secure a Border Gateway Protocol (BGP) peering session and to configure the maximum number of hops that separate two external BGP (eBGP) peers, use the neighbor ttl-security command in address-family or router configuration mode. To disable this feature, use the no form of this command.
neighbor neighbor-address ttl-security hops hop-count
no neighbor neighbor-address ttl-security hops hop-count
Syntax Description
Defaults
No default behavior or values
Command Modes
Address-family configuration
Router configurationCommand History
Usage Guidelines
The neighbor ttl-security command provides a lightweight security mechanism to protect BGP peering sessions from CPU utilization-based attacks. These types of attacks are typically brute force Denial of Service (DoS) attacks that attempt to disable the network by flooding the network with IP packets that contain forged source and destination IP addresses in the packet headers.
This feature leverages designed behavior of IP packets by accepting only IP packets with a TTL count that is equal to or greater than the locally configured value. Accurately forging the TTL count in an IP packet is generally considered to be impossible. Accurately forging a packet to match the TTL count from a trusted peer is not possible without internal access to the source or destination network.
This feature should be configured on each participating router. It secures the BGP session in the incoming direction only and has no effect on outgoing IP packets or the remote router. When this feature is enabled, BGP will establish or maintain a session only if the TTL value in the IP packet header is equal to or greater than the TTL value configured for the peering session. This feature has no effect on the BGP peering session, and the peering session can still expire if keepalive packets are not received. If the TTL value in a received packet is less than the locally configured value, the packet is silently discarded and no Internet Control Message Protocol (ICMP) message is generated. This is designed behavior; a response to a forged packet is not necessary.
To maximize the effectiveness of this feature, the hop-count value should be strictly configured to match the number of hops between the local and external network. However, you should also take path variation into account when configuring this feature for a multihop peering session.
The following restrictions apply to the configuration of this command:
•
•
•
•
Examples
The following example sets the hop count to 2 for a directly connected neighbor. Because the hop-count argument is set to 2, BGP will accept only IP packets with a TTL count in the header that is equal to or greater than 253. If a packet is received with any other TTL value in the IP packet header, the packet will be silently discarded.
neighbor 10.0.0.1 ttl-security hops 2Related Commands
neighbor unsuppress-map
To selectively advertise routes previously suppressed by the aggregate-address command, use the neighbor unsuppress-map command in address family or router configuration mode. To restore the system to the default condition, use the no form of this command.
neighbor {ip-address | peer-group-name} unsuppress-map route-map-name
no neighbor {ip-address | peer-group-name} unsuppress-map route-map-name
Syntax Description
ip-address
IP address of the BGP-speaking neighbor.
peer-group-name
Name of a BGP peer group.
route-map-name
Name of a route map.
Command Default
No routes are unsuppressed.
Command Modes
Address family configuration
Router configurationCommand History
Usage Guidelines
Use of the neighbor unsuppress-map command allows specified suppressed routes to be advertised.
Examples
The following BGP router configuration shows that routes specified by a route map named map1 are suppressed:
access-list 3 deny 172.16.16.6access-list 3 permit anyroute-map map1 permit 10match ip address 3!router bgp 65000network 172.16.0.0neighbor 192.168.1.2 remote-as 40000aggregate-address 172.0.0.0 255.0.0.0 suppress-map map1neighbor 192.168.1.2 unsuppress-map map1neighbor 192.168.1.2 activateThe following example shows the routes specified by internal-map being unsuppressed for neighbor 172.16.16.6:
router bgp 100address-family ipv4 multicastnetwork 172.16.0.0neighbor 172.16.16.6 unsuppress-map internal-mapRelated Commands
neighbor update-source
To have the Cisco IOS software allow Border Gateway Protocol (BGP) sessions to use any operational interface for TCP connections, use the neighbor update-source command in router configuration mode. To restore the interface assignment to the closest interface, which is called the best local address, use the no form of this command.
neighbor {ip-address | ipv6-address[%] | peer-group-name} update-source interface-type interface-number
no neighbor {ip-address | ipv6-address[%] | peer-group-name} update-source interface-type interface-number
Syntax Description
Command Default
Best local address
Command Modes
Router configuration (config-router)
Command History
Usage Guidelines
This command can work in conjunction with the loopback interface feature described in the "Interface Configuration Overview" chapter of the Cisco IOS Interface and Hardware Component Configuration Guide.
If you specify a BGP peer group by using the peer-group-name argument, all the members of the peer group will inherit the characteristic configured with this command.
The neighbor update-source command must be used to enable IPv6 link-local peering for internal or external BGP sessions.
The % keyword is used whenever link-local IPv6 addresses are used outside the context of their interfaces and for these link-local IPv6 addresses you must specify the interface they are on. The syntax becomes <IPv6 local-link address>%<interface name>, for example, FE80::1%Ethernet1/0. Note that the interface type and number must not contain any spaces, and be used in full-length form because name shortening is not supported in this situation. The % keyword and subsequent interface syntax is not used for non-link-local IPv6 addresses.
Examples
The following example sources BGP TCP connections for the specified neighbor with the IP address of the loopback interface rather than the best local address:
router bgp 65000network 172.16.0.0neighbor 172.16.2.3 remote-as 110neighbor 172.16.2.3 update-source Loopback0The following example sources IPv6 BGP TCP connections for the specified neighbor in autonomous system 65000 with the global IPv6 address of loopback interface 0 and the specified neighbor in autonomous system 65400 with the link-local IPv6 address of Fast Ethernet interface 0/0. Note that the link-local IPv6 address of FE80::2 is on Ethernet interface 1/0.
router bgp 65000neighbor 3ffe::3 remote-as 65000neighbor 3ffe::3 update-source Loopback0neighbor fe80::2%Ethernet1/0 remote-as 65400neighbor fe80::2%Ethernet1/0 update-source FastEthernet 0/0address-family ipv6neighbor 3ffe::3 activateneighbor fe80::2%Ethernet1/0 activateexit-address-familyRelated Commands
neighbor activate
Enables the exchange of information with a BGP neighboring router.
neighbor remote-as
Adds an entry to the BGP or multiprotocol BGP neighbor table.
neighbor version
To configure the Cisco IOS software to accept only a particular BGP version, use the neighbor version command in router configuration mode. To use the default version level of a neighbor, use the no form of this command.
neighbor {ip-address | peer-group-name} version number
no neighbor {ip-address | peer-group-name} version number
Syntax Description
Defaults
BGP Version 4
Command Modes
Router configuration
Command History
Usage Guidelines
Entering this command disables dynamic version negotiation.
Note
The Cisco implementation of BGP in Cisco IOS Release 12.0(6)T or later releases supports BGP Version 4 only and does not support dynamic negotiation down to Version 2.If you specify a BGP peer group by using the peer-group-name argument, all the members of the peer group will inherit the characteristic configured with this command.
Examples
The following example locks down to Version 4 of the BGP protocol:
router bgp 109 neighbor 172.16.27.2 version 4Related Commands
neighbor weight
To assign a weight to a neighbor connection, use the neighbor weight command in address family or router configuration mode. To remove a weight assignment, use the no form of this command.
neighbor {ip-address | peer-group-name} weight number
no neighbor {ip-address | peer-group-name} weight number
Syntax Description
ip-address
IP address of the neighbor.
peer-group-name
Name of a BGP peer group.
number
Weight to assign. Acceptable values are from 0 to 65535.
Defaults
Routes learned through another BGP peer have a default weight of 0 and routes sourced by the local router have a default weight of 32768.
Command Modes
Address family
Router configurationCommand History
Usage Guidelines
All routes learned from this neighbor will have the assigned weight initially. The route with the highest weight will be chosen as the preferred route when multiple routes are available to a particular network.
The weights assigned with the set weight route-map command override the weights assigned using the neighbor weight command.
Note
If you specify a BGP peer group by using the peer-group-name argument, all the members of the peer group will inherit the characteristic configured with this command.
Examples
The following router configuration mode example sets the weight of all routes learned via 172.16.12.1 to 50:
router bgp 109 neighbor 172.16.12.1 weight 50The following address family configuration mode example sets the weight of all routes learned via 172.16.12.1 to 50:
router bgp 109address-family ipv4 multicast neighbor 172.16.12.1 weight 50Related Commands
network (BGP and multiprotocol BGP)
To specify the networks to be advertised by the Border Gateway Protocol (BGP) and multiprotocol BGP routing processes, use the network command in address family or router configuration mode. To remove an entry from the routing table, use the no form of this command.
network {network-number [mask network-mask] | nsap-prefix} [route-map map-tag]
no network {network-number [mask network-mask] | nsap-prefix} [route-map map-tag]
Syntax Description
Command Default
No networks are specified.
Command Modes
Address family configuration
Router configurationCommand History
Usage Guidelines
BGP and multiprotocol BGP networks can be learned from connected routes, from dynamic routing, and from static route sources.
The maximum number of network commands you can use is determined by the resources of the router, such as the configured NVRAM or RAM.
Examples
The following example sets up network 10.108.0.0 to be included in the BGP updates:
router bgp 65100network 10.108.0.0The following example sets up network 10.108.0.0 to be included in the multiprotocol BGP updates:
router bgp 64800address family ipv4 multicastnetwork 10.108.0.0The following example advertises NSAP prefix 49.6001 in the multiprotocol BGP updates:
router bgp 64500address-family nsapnetwork 49.6001Related Commands
network backdoor
To specify a backdoor route to a BGP-learned prefix that provides better information about the network, use the network backdoor command in address family or router configuration mode. To remove an address from the list, use the no form of this command.
network ip-address backdoor
no network ip-address backdoor
Syntax Description
Defaults
No network is marked as having a back door.
Command Modes
Address family configuration
Router configurationCommand History
Usage Guidelines
A backdoor network is assigned an administrative distance of 200. The objective is to make Interior Gateway Protocol (IGP) learned routes preferred. A backdoor network is treated as a local network, except that it is not advertised. A network that is marked as a back door is not sourced by the local router, but should be learned from external neighbors. The BGP best path selection algorithm does not change when a network is configured as a back door.
Examples
The following address family configuration example configures network 10.108.0.0 as a local network and network 192.168.7.0 as a backdoor network:
router bgp 109address-family ipv4 multicastnetwork 10.108.0.0network 192.168.7.0 backdoorThe following router configuration example configures network 10.108.0.0 as a local network and network 192.168.7.0 as a backdoor network:
router bgp 109network 10.108.0.0network 192.168.7.0 backdoorRelated Commands
prefix-length-size
To specify the length (in bytes) of the prefix length field of prefixes being advertised to neighbors, use the prefix-length-size command in L2VPN VPLS address-family configuration mode. To restore the default value, use the no form of this command.
prefix-length-size {1|2}
no prefix-length-size
Syntax Description
Command Default
1 byte
Command Modes
L2VPN VPLS address-family configuration (config-router-af)
Command History
Usage Guidelines
You might need to configure this command for interoperability with Juniper's JunOS. If the neighbor is a Juniper JunOS router, change the prefix length size to 2 bytes.
The size of the prefix length field is either 1 or 2 bits or bytes, depending on the address family of the prefix, as follows:
Examples
The following example configures the prefix length size to 2 bytes for L2VPN VPLS prefixes advertised to neighbors:
router bgp 1600address-family l2vpn vplsprefix-length-size 2neighbor 100.16.11.10 activateexit-address-familyRelated Commands
redistribute (BGP to ISO IS-IS)
To redistribute routes from a Border Gateway Protocol (BGP) autonomous system into an International Organization for Standardization (ISO) Intermediate System-to-Intermediate System (IS-IS) routing process, use the redistribute command in router configuration mode. To remove the redistribute command from the configuration file and restore the system to its default condition where the software does not redistribute routes, use the no form of this command.
redistribute protocol autonomous-system-number [route-type] [route-map map-tag]
no redistribute protocol autonomous-system-number [route-type] [route-map map-tag]
Syntax Description
Command Default
Route redistribution is disabled.
Command Modes
Router configuration (config-router)
Command History
Usage Guidelines
The clns keyword must be specified to redistribute NSAP prefix routes from BGP into an ISO IS-IS routing process. This version of the redistribute command is used only under router configuration mode for IS-IS processes.
In redistribution from IGP (for example, ISIS, OSPF, RIP, or EIGRP) to BGP, the support for changing the autonomous system numbers of BGP from one to another is removed.
Examples
The following example configures NSAP prefix routes from BGP autonomous system 64500 to be redistributed into the IS-IS routing process called osi-proc-17:
router isis osi-proc-17redistribute bgp 64500 clnsIn the following example the autonomous system BGP is modified from 200 to 300, this is not supported.
Router#config terminalRouter(config-if)#router eigrp 101Router(config-router)#redistribute bgp 200Router(config-router)#redistribute bgp 300Cannot configure or redistribute to BGP AS 300Please do "no router bgp 200" firstRemove support for autonomous system number 200 before configuring number 300.
Router(config)#no router bgp 200Router(config-router)#redistribute bgp 300Related Commands
redistribute (IP)
To redistribute routes from one routing domain into another routing domain, use the redistribute command in the appropriate configuration mode. To disable redistribution, use the no form of this command.
redistribute protocol [process-id] {level-1 | level-1-2 | level-2} [autonomous-system-number] [metric {metric-value | transparent}] [metric-type type-value]
[match {internal | external 1 | external 2}] [tag tag-value] [route-map map-tag] [subnets] [nssa-only]no redistribute protocol [process-id] {level-1 | level-1-2 | level-2} [autonomous-system-number] [metric {metric-value | transparent}] [metric-type type-value]
[match {internal | external 1 | external 2}] [tag tag-value] [route-map map-tag] [subnets] [nssa-only]Syntax Description
Command Default
Route redistribution is disabled.
Command Modes
Router configuration (config-router)
Address family configuration (config-af)
Address family topology configuration (config-router-af-topology)Command History
Usage Guidelines
Changing or disabling any keyword will not affect the state of other keywords.
A router receiving a link-state protocol with an internal metric will consider the cost of the route from itself to the redistributing router plus the advertised cost to reach the destination. An external metric only considers the advertised metric to reach the destination.
Routes learned from IP routing protocols can be redistributed at Level 1 into an attached area or at Level 2. The level-1-2 keyword allows both Level 1 and Level 2 routes in a single command.
Redistributed routing information must be filtered by the distribute-list out router configuration command. This guideline ensures that only those routes intended by the administrator are passed along to the receiving routing protocol.
Whenever you use the redistribute or the default-information router configuration commands to redistribute routes into an OSPF routing domain, the router automatically becomes an ASBR. However, an ASBR does not, by default, generate a default route into the OSPF routing domain.
When routes are redistributed into OSPF from protocols other than OSPF or BGP, and no metric has been specified with the metric-type keyword and type-value argument, OSPF will use 20 as the default metric. When routes are redistributed into OSPF from BGP, OSPF will use 1 as the default metric. When routes are redistributed from one OSPF process to another OSPF process, Autonomous system (AS) external and not-so-stubby-area (NSSA) routes will use 20 as the default metric. When intra-area and inter-area routes are redistributed between OSPF processes, the internal OSPF metric from the redistribution source process is advertised as the external metric in the redistribution destination process. (This is the only case in which the routing table metric will be preserved when routes are redistributed into OSPF.)
When routes are redistributed into OSPF, only routes that are not subnetted are redistributed if the subnets keyword is not specified.
On a router internal to an NSSA area, the nssa-only keyword causes the originated type-7 NSSA LSAs to have their propagate (P) bit set to zero, which prevents area border routers from translating these LSAs into type-5 external LSAs. On an area border router that is connected to a NSSA and normal areas, the nssa-only keyword causes the routes to be redistributed only into the NSSA areas.
Routes configured with the connected keyword affected by this redistribute command are the routes not specified by the network router configuration command.
You cannot use the default-metric command to affect the metric used to advertise connected routes.
Note
Default redistribution of IGPs or EGP into BGP is not allowed unless the default-information originate router configuration command is specified.
Using the no Form of the redistribute Command
Removing options that you have configured for the redistribute command requires careful use of the no form of the redistribute command to ensure that you obtain the result that you are expecting. See the "Examples" section for more information.
Release 12.2(33)SRB
If you plan to configure the Multi-Topology Routing (MTR) feature, you need to enter the redistribute command in router address family topology configuration mode in order for this OSPF router configuration command to become topology-aware.
4-Byte Autonomous System Number Support
In Cisco IOS Release 12.0(32)SY8, 12.0(33)S3, 12.2(33)SRE, 12.2(33)XNE, 12.2(33)SXI1, Cisco IOS XE Release 2.4, and later releases, the Cisco implementation of 4-byte autonomous system numbers uses asplain—65538 for example—as the default regular expression match and output display format for autonomous system numbers, but you can configure 4-byte autonomous system numbers in both the asplain format and the asdot format as described in RFC 5396. To change the default regular expression match and output display of 4-byte autonomous system numbers to asdot format, use the bgp asnotation dot command.
In Cisco IOS Release 12.0(32)S12, 12.4(24)T, and Cisco IOS XE Release 2.3, the Cisco implementation of 4-byte autonomous system numbers uses asdot—1.2, for example—as the only configuration format, regular expression match, and output display, with no asplain support.
Examples
The following example shows how OSPF routes are redistributed into a BGP domain:
Router(config)# router bgp 109Router(config-router)# redistribute ospfThe following example causes EIGRP routes to be redistributed into an OSPF domain:
Router(config)# router ospf 110Router(config-router)# redistribute eigrpThe following example causes the specified EIGRP process routes to be redistributed into an OSPF domain. The EIGRP-derived metric will be remapped to 100 and RIP routes to 200.
Router(config)# router ospf 109Router(config-router)# redistribute eigrp 108 metric 100 subnetsRouter(config-router)# redistribute rip metric 200 subnetsThe following example configures BGP routes to be redistributed into IS-IS. The link-state cost is specified as 5, and the metric type will be set to external, indicating that it has lower priority than internal metrics.
Router(config)# router isisRouter(config-router)# redistribute bgp 120 metric 5 metric-type externalIn the following example, network 172.16.0.0 will appear as an external link-state advertisement (LSA) in OSPF 1 with a cost of 100 (the cost is preserved):
Router(config)# interface ethernet 0Router(config-if)# ip address 172.16.0.1 255.0.0.0Router(config)# ip ospf cost 100Router(config)# interface ethernet 1Router(config-if)# ip address 10.0.0.1 255.0.0.0!Router(config)# router ospf 1Router(config-router)# network 10.0.0.0 0.255.255.255 area 0Router(config-router)# redistribute ospf 2 subnetRouter(config)# router ospf 2Router(config-router)# network 172.16.0.0 0.255.255.255 area 0The following example shows how BGP routes are redistributed into OSPF and assigned the local 4-byte autonomous system number in asplain format. This example requires Cisco IOS Release 12.0(32)SY8, 12.0(33)S3, 12.2(33)SRE, 12.2(33)SXI1, Cisco IOS XE Release 2.4, or a later release.
Router(config)# router ospf 2Router(config-router)# redistribute bgp 65538The following example removes the connected metric 1000 subnets options from the redistribute connected metric 1000 subnets command and leaves the redistribute connected command in the configuration:
Router(config-router)# no redistribute connected metric 1000 subnets
The following example removes the metric 1000 options from the redistribute connected metric 1000 subnets command and leaves the redistribute connected subnets command in the configuration:
Router(config-router)# no redistribute connected metric 1000
The following example removes the subnets options from the redistribute connected metric 1000 subnets command and leaves the redistribute connected metric 1000 command in the configuration:
Router(config-router)# no redistribute connected subnets
The following example removes the redistribute connected command, and any of the options that were configured for the redistribute connected command, from the configuration:
Router(config-router)# no redistribute connected
The following example shows how EIGRP routes are redistributed into an EIGRP process in a named EIGRP configuration:
Router(config)# router eigrp virtual-nameRouter(config-router)# address-family ipv4 autonomous-system 1Router(config-router-af)# topology baseRouter(config-router-af-topology)# redistribute eigrp 6473 metric 1 1 1 1 1Related Commands
redistribute (ISO IS-IS to BGP)
To redistribute routes from an International Organization for Standardization (ISO) Intermediate System-to-Intermediate System (IS-IS) routing process into a Border Gateway Protocol (BGP) autonomous system, use the redistribute command in address family or router configuration mode. To remove the redistribute command from the configuration file and restore the system to its default condition where the software does not redistribute routes, use the no form of this command.
redistribute protocol [process-id] [route-type] [route-map [map-tag]]
no redistribute protocol [process-id] [route-type] [route-map [map-tag]]
Syntax Description
Command Default
Route redistribution is disabled.
route-type: ip
route-map map-tag: If the route-map argument is not entered, all routes are redistributed; if no
map-tag value is entered, no routes are imported.Command Modes
Address family configuration (Cisco IOS 12.3(8)T and later releases)
Router configuration (T-releases after Cisco IOS 12.3(8)T)Command History
Usage Guidelines
The clns keyword must be specified to redistribute NSAP prefix routes from an ISO IS-IS routing process into BGP. Beginning with Cisco IOS Release 12.3(8)T, this version of the redistribute command is entered only in address family configuration mode for BGP processes.
Examples
Cisco IOS Releases Prior to Release 12.3(8)T
The following example configures CLNS NSAP routes from the IS-IS routing process called osi-proc-6 to be redistributed into BGP:
Router(config)# router bgp 64352Router(config-router)# redistribute isis osi-proc-6 clnsCisco IOS Releases 12.3(8)T and Later Releases
The following example configures CLNS NSAP routes from the IS-IS routing process called osi-proc-15 to be redistributed into BGP:
Router(config)# router bgp 404Router(config-router)# address-family nsapRouter(config-router-af)# redistribute isis osi-proc-15 clnsRelated Commands
redistribute dvmrp
To configure redistribution of Distance Vector Multicast Routing Protocol (DVMRP) routes into multiprotocol BGP, use the redistribute dvmrp command in address family or router configuration mode. To stop such redistribution, use the no form of this command.
redistribute dvmrp [route-map map-name]
no redistribute dvmrp [route-map map-name]
Syntax Description
Defaults
DVMRP routes are not redistributed into multiprotocol BGP.
Command Modes
Address family configuration
Router configurationCommand History
Usage Guidelines
Use this command if you have a subset of DVMRP routes in an autonomous system that you want to take the multiprotocol BGP path. Define a route map to further specify which DVMRP routes get redistributed.
Examples
The following router configuration mode example redistributes DVMRP routes to BGP peers that match access list 1:
router bgp 109redistribute dvmrp route-map dvmrp-into-mbgproute-map dvmrp-into-mbgpmatch ip address 1The following address family configuration mode example redistributes DVMRP routes to multiprotocol BGP peers that match access list 1:
router bgp 109address-family ipv4 multicastredistribute dvmrp route-map dvmrp-into-mbgproute-map dvmrp-into-mbgpmatch ip address 1router bgp
To configure the Border Gateway Protocol (BGP) routing process, use the router bgp command in global configuration mode. To remove a BGP routing process, use the no form of this command.
router bgp autonomous-system-number
no router bgp autonomous-system-number
Syntax Description
Command Default
No BGP routing process is enabled by default.
Command Modes
Global configuration (config)
Command History
Usage Guidelines
This command allows you to set up a distributed routing core that automatically guarantees the loop-free exchange of routing information between autonomous systems.
Prior to January 2009, BGP autonomous system numbers that were allocated to companies were 2-octet numbers in the range from 1 to 65535 as described in RFC 4271, A Border Gateway Protocol 4 (BGP-4). Due to increased demand for autonomous system numbers, the Internet Assigned Number Authority (IANA) will start in January 2009 to allocate four-octet autonomous system numbers in the range from 65536 to 4294967295. RFC 5396, Textual Representation of Autonomous System (AS) Numbers, documents three methods of representing autonomous system numbers. Cisco has implemented the following two methods:
•
•
For details about the third method of representing autonomous system numbers, see RFC 5396.
Note
Asdot Only Autonomous System Number Formatting
In Cisco IOS Release 12.0(32)S12, 12.4(24)T, Cisco IOS XE Release 2.3, and later releases, the 4-octet (4-byte) autonomous system numbers are entered and displayed only in asdot notation, for example, 1.10 or 45000.64000. When using regular expressions to match 4-byte autonomous system numbers the asdot format includes a period which is a special character in regular expressions. A backslash must be entered before the period for example, 1\.14, to ensure the regular expression match does not fail. Table 6 shows the format in which 2-byte and 4-byte autonomous system numbers are configured, matched in regular expressions, and displayed in show command output in Cisco IOS images where only asdot formatting is available.
Asplain as Default Autonomous System Number Formatting
In Cisco IOS Release 12.0(32)SY8, 12.0(33)S3, 12.2(33)SRE, 12.2(33)XNE, 12.2(33)SXI1, Cisco IOS XE Release 2.4, and later releases, the Cisco implementation of 4-byte autonomous system numbers uses asplain as the default display format for autonomous system numbers, but you can configure 4-byte autonomous system numbers in both the asplain and asdot format. In addition, the default format for matching 4-byte autonomous system numbers in regular expressions is asplain, so you must ensure that any regular expressions to match 4-byte autonomous system numbers are written in the asplain format. If you want to change the default show command output to display 4-byte autonomous system numbers in the asdot format, use the bgp asnotation dot command under router configuration mode. When the asdot format is enabled as the default, any regular expressions to match 4-byte autonomous system numbers must be written using the asdot format, or the regular expression match will fail. Table 7 and Table 8 show that although you can configure 4-byte autonomous system numbers in either asplain or asdot format, only one format is used to display show command output and control 4-byte autonomous system number matching for regular expressions, and the default is asplain format. To display 4-byte autonomous system numbers in show command output and to control matching for regular expressions in the asdot format, you must configure the bgp asnotation dot command. After enabling the bgp asnotation dot command, a hard reset must be initiated for all BGP sessions by entering the clear ip bgp * command.
Note
Reserved and Private Autonomous System Numbers
In Cisco IOS Release 12.0(32)S12, 12.0(32)SY8, 12.2(33)SRE, 12.2(33)XNE, 12.2(33)SXI1, 12.4(24)T, Cisco IOS XE Release 2.3 and later releases, the Cisco implementation of BGP supports RFC 4893. RFC 4893 was developed to allow BGP to support a gradual transition from 2-byte autonomous system numbers to 4-byte autonomous system numbers. A new reserved (private) autonomous system number, 23456, was created by RFC 4893 and this number cannot be configured as an autonomous system number in the Cisco IOS CLI.
RFC 5398, Autonomous System (AS) Number Reservation for Documentation Use, describes new reserved autonomous system numbers for documentation purposes. Use of the reserved numbers allow configuration examples to be accurately documented and avoids conflict with production networks if these configurations are literally copied. The reserved numbers are documented in the IANA autonomous system number registry. Reserved 2-byte autonomous system numbers are in the contiguous block, 64496 to 64511 and reserved 4-byte autonomous system numbers are from 65536 to 65551 inclusive.
Private 2-byte autonomous system numbers are still valid in the range from 64512 to 65534 with 65535 being reserved for special use. Private autonomous system numbers can be used for internal routing domains but must be translated for traffic that is routed out to the Internet. BGP should not be configured to advertise private autonomous system numbers to external networks. Cisco IOS software does not remove private autonomous system numbers from routing updates by default. We recommend that ISPs filter private autonomous system numbers.
Note
Examples
The following example configures a BGP process for autonomous system 45000 and configures two external BGP neighbors in different autonomous systems using 2-byte autonomous system numbers:
router bgp 45000neighbor 192.168.1.2 remote-as 40000neighbor 192.168.3.2 remote-as 50000neighbor 192.168.3.2 description finance!address-family ipv4neighbor 192.168.1.2 activateneighbor 192.168.3.2 activateno auto-summaryno synchronizationnetwork 172.17.1.0 mask 255.255.255.0exit-address-familyThe following example configures a BGP process for autonomous system 65538 and configures two external BGP neighbors in different autonomous systems using 4-byte autonomous system numbers in asplain notation. This example is supported i n Cisco IOS Release 12.0(32)SY8, 12.0(33)S3, 12.2(33)SRE, 12.2(33)XNE, 12.2(33)SXI1, Cisco IOS XE Release 2.4, and later releases.
router bgp 65538neighbor 192.168.1.2 remote-as 65536neighbor 192.168.3.2 remote-as 65550neighbor 192.168.3.2 description finance!address-family ipv4neighbor 192.168.1.2 activateneighbor 192.168.3.2 activateno auto-summaryno synchronizationnetwork 172.17.1.0 mask 255.255.255.0exit-address-familyThe following example configures a BGP process for autonomous system 1.2 and configures two external BGP neighbors in different autonomous systems using 4-byte autonomous system numbers in asdot notation. This example is supported in Cisco IOS Release 12.0(32)SY8, 12.0(32)S12, 12.2(33)SRE, 12.2(33)XNE, 12.2(33)SXI1, 12.4(24)T, and Cisco IOS XE Release 2.3, and later releases.
router bgp 1.2neighbor 192.168.1.2 remote-as 1.0neighbor 192.168.3.2 remote-as 1.14neighbor 192.168.3.2 description finance!address-family ipv4neighbor 192.168.1.2 activateneighbor 192.168.3.2 activateno auto-summaryno synchronizationnetwork 172.17.1.0 mask 255.255.255.0exit-address-familyRelated Commands
route-server-context
To create a route-server context in order to provide flexible policy handling for a BGP route server, use the route-server-context command in router configuration mode. To remove the route server context, use the no form of this command.
route-server-context context-name
no route-server-context context-name
Syntax Description
Command Default
No route server context exists.
Command Modes
Router configuration (config-router)
Command History
Usage Guidelines
Flexible (customized) policy support for a BGP route server is made possible with the use of the route-server-context command. The route-server-context command creates a context, which represents the virtual table used to store prefixes and paths that require special handling due to individualized policy configurations.
The context is referenced by the BGP neighbors assigned to use that context (in the neighbor route-server-client command). Thus, multiple neighbors sharing the same policy can share the same route server context.
In order to configure flexible policy handling, create a route server context, which includes an import map. The import map references a standard route map.
Examples
In the following example, the local router is a BGP route server. Its neighbors at 10.10.10.12 and 10.10.10.13 are its route server clients. A route server context named ONLY_AS27_CONTEXT is created and applied to the neighbor at 10.10.10.13. The context uses an import map that references a route map named only_AS27_routemap. The route map matches routes permitted by access list 27. Access list 27 permits routes that have 27 in the autonomous system path.
router bgp 65000route-server-context ONLY_AS27_CONTEXTaddress-family ipv4 unicastimport-map only_AS27_routemapexit-address-familyexit-route-server-context!neighbor 10.10.10.12 remote-as 12neighbor 10.10.10.12 description Peer12neighbor 10.10.10.13 remote-as 13neighbor 10.10.10.13 description Peer13neighbor 10.10.10.21 remote-as 21neighbor 10.10.10.27 remote-as 27!address-family ipv4neighbor 10.10.10.12 activateneighbor 10.10.10.12 route-server-clientneighbor 10.10.10.13 activateneighbor 10.10.10.13 route-server-client context ONLY_AS27_CONTEXTneighbor 10.10.10.21 activateneighbor 10.10.10.27 activateexit-address-family!ip as-path access-list 27 permit 27!route-map only_AS27_routemap permit 10match as-path 27!Related Commands
scope
To define the scope for a Border Gateway Protocol (BGP) routing session and to enter router scope configuration mode, use the scope command in router configuration mode. To remove the scope configuration, use the no form of this command.
scope {global | vrf vrf-name}
no scope {global | vrf vrf-name}
Syntax Description
global
Configures BGP to use the global routing table or a specific topology table.
vrf
Configures BGP to use a specific VRF routing table.
vrf-name
Name of an existing VRF.
Command Default
No scope is defined for a BGP routing session.
Command Modes
Router configuration
Command History
Usage Guidelines
A new configuration hierarchy, named scope, has been introduced into the BGP protocol. To implement Multi-Topology Routing (MTR) support for BGP, the scope hierarchy is required, but the scope hierarchy is not limited to MTR use. The scope hierarchy introduces some new configuration modes such as router scope configuration mode. Router scope configuration mode is entered by configuring the scope command in router configuration mode, and a collection of routing tables is created when this command is entered. The scope is configured to isolate routing calculation for a single network (globally) or on a per-VRF basis, and BGP commands configured in routing scope configuration mode are referred to as scoped commands. The scope hierarchy can contain one or more address families.
The BGP command-line interface (CLI) has been modified to provide backwards compatibility for pre-MTR BGP configuration and to provide a hierarchal implementation of MTR. From router scope configuration mode, MTR is configured first by entering the address-family command to enter the desired address family and then by entering the topology command to define the topology
Note
Examples
The following example defines a global scope that includes both unicast and multicast topology configurations. Another scope is specifically defined only for the VRF named DATA.
Router(config)# router bgp 45000Router(config-router)# scope globalRouter(config-router-scope)# bgp default ipv4-unicastRouter(config-router-scope)# neighbor 172.16.1.2 remote-as 45000Router(config-router-scope)# neighbor 192.168.3.2 remote-as 50000Router(config-router-scope)# address-family ipv4 unicastRouter(config-router-scope-af)# topology VOICERouter(config-router-scope-af)# bgp tid 100Router(config-router-scope-af)# neighbor 172.16.1.2 activateRouter(config-router-scope-af)# exitRouter(config-router-scope)# address-family ipv4 multicastRouter(config-router-scope-af)# topology baseRouter(config-router-scope-af-topo)# neighbor 192.168.3.2 activateRouter(config-router-scope-af-topo)# exitRouter(config-router-scope-af)# exitRouter(config-router-scope)# exitRouter(config-router)# scope vrf DATARouter(config-router-scope)# neighbor 192.168.1.2 remote-as 40000Router(config-router-scope)# address-family ipv4Router(config-router-scope-af)# neighbor 192.168.1.2 activateRouter(config-router-scope-af)# endRelated Commands
bgp tid
Configures BGP to accept routes with a specified topology ID.
topology (BGP)
Configures a process to route IP traffic under the specified topology instance.
set as-path
To modify an autonomous system path for BGP routes, use the set as-path command in route-map configuration mode. To not modify the autonomous system path, use the no form of this command.
set as-path {tag | prepend as-path-string}
no set as-path {tag | prepend as-path-string}
Syntax Description
Command Default
An autonomous system path is not modified.
Command Modes
Route-map configuration (config-route-map)
Command History
Usage Guidelines
The only global BGP metric available to influence the best path selection is the autonomous system path length. By varying the length of the autonomous system path, a BGP speaker can influence the best path selection by a peer further away.
By allowing you to convert the tag into an autonomous system path, the set as-path tag variation of this command modifies the autonomous system length. The set as-path prepend variation allows you to "prepend" an arbitrary autonomous system path string to BGP routes. Usually the local autonomous system number is prepended multiple times, increasing the autonomous system path length.
In Cisco IOS Release 12.0(32)SY8, 12.0(33)S3, 12.2(33)SRE, 12.2(33)XNE, 12.2(33)SXI1, Cisco IOS XE Release 2.4, and later releases, the Cisco implementation of 4-byte autonomous system numbers uses asplain—65538 for example—as the default regular expression match and output display format for autonomous system numbers, but you can configure 4-byte autonomous system numbers in both the asplain format and the asdot format as described in RFC 5396. To change the default regular expression match and output display of 4-byte autonomous system numbers to asdot format, use the bgp asnotation dot command followed by the clear ip bgp * command to perform a hard reset of all current BGP sessions.
In Cisco IOS Release 12.0(32)S12, 12.4(24)T, and Cisco IOS XE Release 2.3, the Cisco implementation of 4-byte autonomous system numbers uses asdot—1.2 for example—as the only configuration format, regular expression match, and output display, with no asplain support.
Examples
The following example converts the tag of a redistributed route into an autonomous system path:
route-map set-as-path-from-tagset as-path tag!router bgp 100redistribute ospf 109 route-map set-as-path-from-tagThe following example prepends 100 100 100 to all the routes that are advertised to 10.108.1.1:
route-map set-as-pathmatch as-path 1set as-path prepend 100 100 100!router bgp 100neighbor 10.108.1.1 route-map set-as-path outThe following example prepends 65538, 65538, and 65538 to all the routes that are advertised to 192.168.1.2. This example requires Cisco IOS Release 12.0(32)SY8, 12.0(33)S3, 12.2(33)SRE, 12.2(33)XNE, 12.2(33)SXI1, Cisco IOS XE Release 2.4, or a later release.
route-map set-as-pathmatch as-path 1.1set as-path prepend 65538 65538 65538exitrouter bgp 65538neighbor 192.168.1.2 route-map set-as-path outRelated Commands
set comm-list delete
To remove communities from the community attribute of an inbound or outbound update, use the set comm-list delete command in route-map configuration mode. To remove a previous set comm-list delete command, use the no form of this command.
set comm-list {community-list-number | community-list-name} delete
no set comm-list {community-list-number | community-list-name} delete
Syntax Description
Command Default
No communities are removed.
Command Modes
Route-map configuration
Command History
Usage Guidelines
This set route-map configuration command removes communities from the community attribute of an inbound or outbound update using a route map to filter and determine the communities to be deleted. Depending upon whether the route map is applied to the inbound or outbound update for a neighbor, each community that passes the route map permit clause and matches the given community list will be removed from the community attribute being received from or sent to the Border Gateway Protocol (BGP) neighbor.
Each entry of a standard community list should list only one community when used with the set comm-list delete command. For example, in order to be able to delete communities 10:10 and 10:20, you must use the following format to create the entries:
ip community-list 500 permit 10:10 ip community-list 500 permit 10:20The following format for a community list entry, while acceptable otherwise, does not work with the set comm-list delete command:
config ip community-list 500 permit 10:10 10:20When both the set community community-number and set comm-list delete commands are configured in the same sequence of a route map attribute, the deletion operation (set comm-list delete) is performed before the set operation (set community community-number).
Examples
In the following example, the communities 100:10 and 100:20 (if present) will be deleted from updates received from 172.16.233.33. Also, except for 100:50, all communities beginning with 100: will be deleted from updates sent to 172.16.233.33.
router bgp 100 neighbor 172.16.233.33 remote-as 120 neighbor 172.16.233.33 route-map ROUTEMAPIN in neighbor 172.16.233.33 route-map ROUTEMAPOUT out ! ip community-list 500 permit 100:10 ip community-list 500 permit 100:20 ! ip community-list 120 deny 100:50 ip community-list 120 permit 100:.* ! route-map ROUTEMAPIN permit 10 set comm-list 500 delete ! route-map ROUTEMAPOUT permit 10 set comm-list 120 deleteRelated Commands
set community
To set the BGP communities attribute, use the set community route map configuration command. To delete the entry, use the no form of this command.
set community {community-number [additive] [well-known-community] | none}
no set community
Syntax Description
Command Default
No BGP communities attributes exist.
Command Modes
Route-map configuration
Command History
Usage Guidelines
You must have a match clause (even if it points to a "permit everything" list) if you want to set tags.
Use the route-map global configuration command, and the match and set route map configuration commands, to define the conditions for redistributing routes from one routing protocol into another. Each route-map command has a list of match and set commands associated with it. The match commands specify the match criteria—the conditions under which redistribution is allowed for the current route-map command. The set commands specify the set actions—the particular redistribution actions to perform if the criteria enforced by the match commands are met. The no route-map command deletes the route map.
The set route map configuration commands specify the redistribution set actions to be performed when all of the match criteria of a route map are met. When all match criteria are met, all set actions are performed.
Examples
In the following example, routes that pass the autonomous system path access list 1 have the community set to 109. Routes that pass the autonomous system path access list 2 have the community set to no-export (these routes will not be advertised to any external BGP [eBGP] peers).
route-map set_community 10 permitmatch as-path 1set community 109route-map set_community 20 permitmatch as-path 2set community no-exportIn the following similar example, routes that pass the autonomous system path access list 1 have the community set to 109. Routes that pass the autonomous system path access list 2 have the community set to local-as (the router will not advertise this route to peers outside the local autonomous system.
route-map set_community 10 permitmatch as-path 1set community 109route-map set_community 20 permitmatch as-path 2set community local-asRelated Commands
set dampening
To set the BGP route dampening factors, use the set dampening route map configuration command. To disable this function, use the no form of this command.
set dampening half-life reuse suppress max-suppress-time
no set dampening
Syntax Description
Defaults
This command is disabled by default.
Command Modes
Route-map configuration
Command History
Usage Guidelines
Use the route-map global configuration command, and the match and set route-map configuration commands, to define the conditions for redistributing routes from one routing protocol into another. Each route-map command has a list of match and set commands associated with it. The match commands specify the match criteria—the conditions under which redistribution is allowed for the current route-map command. The set commands specify the set actions—the particular redistribution actions to perform if the criteria enforced by the match commands are met. The no route-map command deletes the route map.
When a BGP peer is reset, the route is withdrawn and the flap statistics cleared. In this instance, the withdrawal does not incur a penalty even though route flap dampening is enabled.
Examples
The following example sets the half life to 30 minutes, the reuse value to 1500, the suppress value to 10000; and the maximum suppress time to 120 minutes:
route-map tagmatch as path 10set dampening 30 1500 10000 120!router bgp 100neighbor 172.16.233.52 route-map tag inRelated Commands
set extcommunity
To set Border Gateway Protocol (BGP) extended community attributes, use the set extcommunity command in route-map configuration mode. To delete the entry, use the no form of this command.
set extcommunity {rt [extended-community-value] [additive] | soo [extended-community-value]}
no set extcommunity
Syntax Description
Command Default
Specifying new route targets with the rt keyword replaces existing route targets by default, unless the additive keyword is used. The use of the additive keyword adds the new route target to the existing route target list but does not replace any existing route targets.
Command Modes
Route-map configuration (config-route-map)
Command History
Usage Guidelines
Extended community attributes are used to configure, filter, and identify routes for virtual routing and forwarding instances (VRFs) and Multiprotocol Label Switching (MPLS) Virtual Private Networks (VPNs).
The set extcommunity command is used to configure set clauses that use extended community attributes in route maps. All of the standard rules of match and set clauses apply to the configuration of extended community attributes.
The route target (RT) extended community attribute is configured with the rt keyword. This attribute is used to identify a set of sites and VRFs that may receive routes that are tagged with the configured route target. Configuring the route target extended attribute with a route allows that route to be placed in the per-site forwarding tables that are used for routing traffic that is received from corresponding sites.
The site of origin (SOO) extended community attribute is configured with the soo keyword. This attribute uniquely identifies the site from which the Provider Edge (PE) router learned the route. All routes learned from a particular site must be assigned the same SOO extended community attribute, whether a site is connected to a single PE router or multiple PE routers. Configuring this attribute prevents routing loops from occurring when a site is multihomed. The SOO extended community attribute is configured on the interface and is propagated into BGP through redistribution. The SOO can be applied to routes that are learned from VRFs. The SOO should not be configured for stub sites or sites that are not multihomed.
In Cisco IOS Release 12.0(32)SY8, 12.0(33)S3, 12.2(33)SRE, 12.2(33)XNE, 12.2(33)SXI1, Cisco IOS XE Release 2.4, and later releases, the Cisco implementation of 4-byte autonomous system numbers uses asplain—65538 for example—as the default regular expression match and output display format for autonomous system numbers, but you can configure 4-byte autonomous system numbers in both the asplain format and the asdot format as described in RFC 5396. To change the default regular expression match and output display of 4-byte autonomous system numbers to asdot format, use the bgp asnotation dot command followed by the clear ip bgp * command to perform a hard reset of all current BGP sessions.
In Cisco IOS Release 12.0(32)S12, 12.4(24)T, and Cisco IOS XE Release 2.3, the Cisco implementation of 4-byte autonomous system numbers uses asdot—1.2 for example—as the only configuration format, regular expression match, and output display, with no asplain support.
Examples
The following example sets the route target to extended community attribute 100:2 for routes that are permitted by the route map:
Router(config)# access-list 2 permit 192.168.78.0 255.255.255.0Router(config)# route-map MAP_NAME permit 10Router(config-route-map)# match ip-address 2Router(config-route-map)# set extcommunity rt 100:2The following example sets the route target to extended community attribute 100:3 for routes that are permitted by the route map. The use of the additive keyword adds route target 100:3 to the existing route target list but does not replace any existing route targets.
Router(config)# access-list 3 permit 192.168.79.0 255.255.255.0Router(config)# route-map MAP_NAME permit 10Router(config-route-map)# match ip-address 3Router(config-route-map)# set extcommunity rt 100:3 additive
Note
The following example sets the site of origin to extended community attribute 100:4 for routes that are permitted by the route map:
Router(config)# access-list 4 permit 192.168.80.0 255.255.255.0Router(config)# route-map MAP_NAME permit 10Router(config-route-map)# match ip-address 4Router(config-route-map)# set extcommunity soo 100:4In IPv6, the following example sets the SoO to extended community attribute 100:28 for routes that are permitted by the route map:
(config)# router bgp 100
(config-router)# address-family ipv6 vrf red
(config-router-af)# neighbor 8008::72a route-map setsoo in
(config-router-af)# exit
(config-router)# route-map setsoo permit 10
(config-router)# set extcommnunity soo 100:28
The following example available in Cisco IOS Release 12.0(32)SY8, 12.0(33)S3, 12.2(33)SRE, 12.2(33)XNE, 12.2(33)SXI1, Cisco IOS XE Release 2.4, and later releases, shows how to create a VRF with a route-target that uses a 4-byte autonomous system number, 65537 in asplain format, and how to set the route-target to extended community value 65537:100 for routes that are permitted by the route map.
Router(config)# ip vrf vpn_red
Router(config-vrf)# rd 64500:100
Router(config-vrf)# route-target both 65537:100
Router(config-vrf)# exit
Router(config)# route-map rt_map permit 10
Router(config-route-map)# set extcommunity rt 65537:100
Router(config-route-map)# end
The following example available in Cisco IOS Release 12.0(32)SY8, 12.0(32)S12, 12.2(33)SRE, 12.2(33)XNE, 12.2(33)SXI1, 12.4(24)T, Cisco IOS XE Release 2.3, and later releases, shows how to create a VRF with a route-target that uses a 4-byte autonomous system number, 1.1 in asdot format, and how to set the SoO to extended community attribute 1.1:100 for routes that are permitted by the route map.
Router(config)# ip vrf vpn_red
Router(config-vrf)# rd 64500:100
Router(config-vrf)# route-target both 1.1:100
Router(config-vrf)# exit
Router(config)# route-map soo_map permit 10
Router(config-route-map)# set extcommunity soo 1.1:100
Router(config-route-map)# end
Related Commands
set extcommunity cost
To create a set clause to apply the cost community attribute to routes that pass through a route map, use the set extcommunity cost command in route-map configuration mode. To delete the cost community set clause, use the no form of this command.
set extcommunity cost [igp | pre-bestpath] community-id cost-value
no set extcommunity cost [igp] community-id cost-value
Syntax Description
Command Default
The default cost value is applied to routes that are not configured with the cost community attribute when cost community filtering is enabled. The default cost-value is half of the maximum value (4294967295) or 2147483647.
Command Modes
Route-map configuration
Command History
Usage Guidelines
The cost community attribute is applied to internal routes by configuring the set extcommunity cost command in a route map. The cost community set clause is configured with a cost community ID number (0-255) and a cost community number value (0-4294967295). The path with the lowest cost community number is preferred. In the case where two paths have been configured with the same cost community value, the path selection process will then prefer the path with the lower community ID.
The BGP Cost Community feature can be configured only within the same autonomous-system or confederation. The cost community is a non-transitive extended community. The cost community is passed to internal BGP (iBGP) and confederation peers only and is not passed to external BGP (eBGP) peers. The cost community allows you to customize the local preference and best path selection process for specific paths. The cost extended community attribute is propagated to iBGP peers when extended community exchange is enabled with the neighbor send-community command.
The following commands can be used to apply the route map with the cost community set clause:
•
•
•
•
•
Multiple cost community set clauses may be configured with the set extcommunity cost command in a single route map block or sequence. However, each set clause must be configured with a different ID value for each point of insertion (POI).
Aggregate routes and multipaths are supported by the BGP Cost Community feature. The cost community attribute can be applied to either type of route. The cost community attribute is passed to the aggregate or multipath route from component routes that carry the cost community attribute. Only unique IDs are passed, and only the highest cost of any individual component route will be applied to the aggregate on a per-ID basis. If multiple component routes contain the same ID, the highest configured cost is applied to the route. If one or more component routes does not carry the cost community attribute or if the component routes are configured with different IDs, then the default value (2147483647) will be advertised for the aggregate or multipath route.
Note
Support for EIGRP MPLS VPN Back Door Links
The "pre-bestpath" point of insertion (POI) has been introduced in the BGP Cost Community feature to support mixed EIGRP VPN network topologies that contain VPN and backdoor links. This POI is applied automatically to EIGRP routes that are redistributed into BGP. The "pre-best path" POI carries the EIGRP route type and metric. This POI influences the best path calculation process by influencing BGP to consider this POI before any other comparison step. No configuration is required. This feature is enabled automatically for EIGRP VPN sites when a supporting is installed to a PE, CE, or back door router.
Examples
The following example configuration shows the configuration of the set extcommunity cost command. The following example applies the cost community ID of 1 and cost community value of 100 to routes that are permitted by the route map. This configuration will cause the best path selection process to prefer this route over other equal cost paths that were not permitted by this route map sequence.
Router(config)# router bgp 50000Router(config-router)# neighbor 10.0.0.1 remote-as 50000Router(config-router)# neighbor 10.0.0.1 update-source Loopback 0Router(config-router)# address-family ipv4Router(config-router-af)# neighbor 10.0.0.1 activateRouter(config-router-af)# neighbor 10.0.0.1 route-map COST1 inRouter(config-router-af)# neighbor 10.0.0.1 send-community bothRouter(config-router-af)# exitRouter(config)# route-map COST1 permit 10Router(config-route-map)# match ip-address 1Router(config-route-map)# set extcommunity cost 1 100Related Commands
set ip next-hop (BGP)
To indicate where to output packets that pass a match clause of a route map for policy routing, use the set ip next-hop command in route-map configuration mode. To delete an entry, use the no form of this command.
set ip next-hop ip-address [... ip-address] [peer-address]
no set ip next-hop ip-address [... ip-address] [peer-address]
Syntax Description
ip-address
IP address of the next hop to which packets are output. It need not be an adjacent router.
peer-address
(Optional) Sets the next hop to be the BGP peering address.
Defaults
This command is disabled by default.
Command Modes
Route-map configuration
Command History
Usage Guidelines
An ellipsis (...) in the command syntax indicates that your command input can include multiple values for the ip-address argument.
Use the ip policy route-map interface configuration command, the route-map global configuration command, and the match and set route-map configuration commands to define the conditions for policy routing packets. The ip policy route-map command identifies a route map by name. Each route-map command has a list of match and set commands associated with it. The match commands specify the match criteria—the conditions under which policy routing occurs. The set commands specify the set actions—the particular routing actions to perform if the criteria enforced by the match commands are met.
If the first next hop specified with the set ip next-hop command is down, the optionally specified IP addresses are tried in turn.
When the set ip next-hop command is used with the peer-address keyword in an inbound route map of a BGP peer, the next hop of the received matching routes will be set to be the neighbor peering address, overriding any third-party next hops. So the same route map can be applied to multiple BGP peers to override third-party next hops.
When the set ip next-hop command is used with the peer-address keyword in an outbound route map of a BGP peer, the next hop of the advertised matching routes will be set to be the peering address of the local router, thus disabling the next hop calculation. The set ip next-hop command has finer granularity than the (per-neighbor) neighbor next-hop-self command, because you can set the next hop for some routes, but not others. The neighbor next-hop-self command sets the next hop for all routes sent to that neighbor.
The set clauses can be used in conjunction with one another. They are evaluated in the following order:
1.
2.
3.
4.
Note
Examples
In the following example, three routers are on the same FDDI LAN (with IP addresses 10.1.1.1, 10.1.1.2, and 10.1.1.3). Each is in a different autonomous system. The set ip next-hop peer-address command specifies that traffic from the router (10.1.1.3) in remote autonomous system 300 for the router (10.1.1.1) in remote autonomous system 100 that matches the route map is passed through the router bgp 200, rather than sent directly to the router (10.1.1.1) in autonomous system 100 over their mutual connection to the LAN.
router bgp 200neighbor 10.1.1.3 remote-as 300neighbor 10.1.1.3 route-map set-peer-address outneighbor 10.1.1.1 remote-as 100route-map set-peer-address permit 10set ip next-hop peer-addressRelated Commands
set metric (BGP-OSPF-RIP)
To set the metric value for a routing protocol, use the set metric command in route-map configuration mode. To return to the default metric value, use the no form of this command.
set metric metric-value
no set metric metric-value
Syntax Description
metric-value
Metric value; an integer from -294967295 to 294967295. This argument applies to all routing protocols except Enhanced Interior Gateway Routing Protocol (EIGRP).
Defaults
The dynamically learned metric value.
Command Modes
Route-map configuration
Command History
Usage Guidelines
We recommend that you consult your Cisco technical support representative before changing the default value.
Use the route-map global configuration command, and the match and set route-map configuration commands, to define the conditions for redistributing routes from one routing protocol into another. Each route-map command has a list of match and set commands associated with it. The match commands specify the match criteria—the conditions under which redistribution is allowed for the current route-map command. The set commands specify the set actions—the particular redistribution actions to perform if the criteria enforced by the match commands are met. The no route-map command deletes the route map.
The set route-map configuration commands specify the redistribution set actions to be performed when all the match criteria of a route map are met. When all match criteria are met, all set actions are performed.
Examples
The following example sets the metric value for the routing protocol to 100:
route-map set-metricset metric 100Related Commands
set metric-type internal
To set the Multi Exit Discriminator (MED) value on prefixes advertised to external BGP (eBGP) neighbors to match the Interior Gateway Protocol (IGP) metric of the next hop, use the set metric-type internal command in route-map configuration mode. To return to the default, use the no form of this command.
set metric-type internal
no set metric-type internal
Syntax Description
This command has no arguments or keywords.
Defaults
This command is disabled by default.
Command Modes
Route-map configuration
Command History
Usage Guidelines
This command will cause BGP to advertise a MED value that corresponds to the IGP metric associated with the next hop of the route. This command applies to generated, internal BGP (iBGP)-, and eBGP-derived routes.
If this command is used, multiple BGP speakers in a common autonomous system can advertise different MED values for a particular prefix. Also, note that if the IGP metric changes, BGP will readvertise the route every 10 minutes.
Use the route-map global configuration command and the match and set route-map configuration commands to define the conditions for redistributing routes from one routing protocol into another. Each route-map command has a list of match and set commands associated with it. The match commands specify the match criteria—the conditions under which redistribution is allowed for the current route-map command. The set commands specify the set actions—the particular redistribution actions to perform if the criteria enforced by the match commands are met. The no route-map command deletes the route map.
The set route-map configuration commands specify the redistribution set actions to be performed when all of the match criteria of the route map are met. When all match criteria are met, all set actions are performed.
Note
Examples
In the following example, the MED value for all the advertised routes to neighbor 172.16.2.3 is set to the corresponding IGP metric of the next hop:
router bgp 109network 172.16.0.0neighbor 172.16.2.3 remote-as 200neighbor 172.16.2.3 route-map setMED out!route-map setMED permit 10match as-path 1set metric-type internal!ip as-path access-list 1 permit .*Related Commands
route-map (IP)
Defines the conditions for redistributing routes from one routing protocol into another, or enables policy routing.
set origin (BGP)
To set the BGP origin code, use the set origin command in route-map configuration mode. To delete an entry, use the no form of this command.
set origin {igp | egp autonomous-system-number | incomplete}
no set origin {igp | egp autonomous-system-number | incomplete}
Syntax Description
Command Default
The origin of the route is based on the path information of the route in the main IP routing table.
Command Modes
Route-map configuration (config-route-map)
Command History
Usage Guidelines
You must have a match clause (even if it points to a "permit everything" list) if you want to set the origin of a route. Use this command to set a specific origin when a route is redistributed into BGP. When routes are redistributed, the origin is usually recorded as incomplete, identified with a ? in the BGP table.
Use the route-map global configuration command, and the match and set route-map configuration commands, to define the conditions for redistributing routes from one routing protocol into another. Each route-map command has a list of match and set commands associated with it. The match commands specify the match criteria—the conditions under which redistribution is allowed for the current route-map command. The set commands specify the set actions—the particular redistribution actions to perform if the criteria enforced by the match commands are met. The no route-map command deletes the route map.
The set route-map configuration commands specify the redistribution set actions to be performed when all of the match criteria of a route map are met. When all match criteria are met, all set actions are performed.
Examples
The following example sets the origin of routes that pass the route map to IGP:
route-map set_originmatch as-path 10set origin igpRelated Commands
set traffic-index
To indicate how to classify packets that pass a match clause of a route map for Border Gateway Protocol (BGP) policy accounting, use the set traffic-index command in route-map configuration mode. To delete an entry, use the no form of this command.
set traffic-index bucket-number
no set traffic-index bucket-number
Syntax Description
bucket-number
Number that represents a bucket into which packet and byte statistics are collected for a specific traffic classification. The range is from 1 to 64.
Command Default
Routing traffic is not classified.
Command Modes
Route-map configuration
Command History
Usage Guidelines
Use the set traffic-index route-map configuration command, the route-map global configuration command, and a match route-map configuration command to define the conditions for BGP policy accounting. The match commands specify the match criteria—the conditions under which policy routing occurs. The set traffic-index command specifies the set actions—the particular routing actions to perform if the criteria specified by the match commands are met.
Examples
In the following example, an index for BGP policy accounting is set according to autonomous system path criteria:
route-map buckets permit 10match as-path 1set traffic-index 1Related Commands
set weight
To specify the BGP weight for the routing table, use the set weight command in route-map configuration mode. To delete an entry, use the no form of this command.
set weight number
no set weight number
Syntax Description
Defaults
The weight is not changed by the specified route map.
Command Modes
Route-map configuration
Command History
Usage Guidelines
The implemented weight is based on the first matched autonomous system path. Weights indicated when an autonomous system path is matched override the weights assigned by global neighbor commands. In other words, the weights assigned with the set weight route-map configuration command override the weights assigned using the neighbor weight command.
Examples
The following example sets the BGP weight for the routes matching the autonomous system path access list to 200:
route-map set-weightmatch as-path 10set weight 200Related Commands
show bgp all community
To display routes for all address families belonging to a particular Border Gateway Protocol (BGP) community, use the show bgp all community command in user EXEC or privileged EXEC configuration mode.
show bgp all community [community-number...[community-number]] [local-as] [no-advertise] [no-export] [exact-match]
Syntax Description
Command Modes
User EXEC (>)
Privileged EXEC (#)Command History
Usage Guidelines
You can enter the local-as, no-advertise and no-export keywords in any order. You can set the communities using the set community command.
When using the bgp all community command, be sure to enter the numerical communities before the well-known communities.
For example, the following string is not valid:
Router# show bgp all community local-as 111:12345
Use the following string instead:
Router# show bgp all community 111:12345 local-as
Examples
The following is sample output from the show bgp all community command, specifying communities of 1, 2345, and 6789012:
Router# show bgp all community 1 2345 6789012 no-advertise local-as no-export exact-matchFor address family: IPv4 UnicastBGP table version is 5, local router ID is 30.0.0.5Status codes: s suppressed, d damped, h history, * valid, > best, i - internal,r RIB-failure, S StaleOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path*> 10.0.3.0/24 10.0.0.4 0 4 3 ?*> 10.1.0.0/16 10.0.0.4 0 0 4 ?*> 10.12.34.0/24 10.0.0.6 0 0 6 ?Table 9 describes the significant fields shown in the display.
Related Commands
set community
Sets BGP communities.
set local-preference
Specifies a preference value for the autonomous system path.
show bgp all neighbors
To display information about Border Gateway Protocol (BGP) connections to neighbors of all address families, use the show bgp all neighbors command in user EXEC or privileged EXEC mode.
show bgp all neighbors [ip-address | ipv6-address] [advertised-routes | dampened-routes | flap-statistics | paths [reg-exp] | policy [detail] | received prefix-filter | received-routes | routes]
Syntax Description
Command Default
The output of this command displays information for all neighbors.
Command Modes
User EXEC (>)
Privileged EXEC (#)Command History
Usage Guidelines
Use the show bgp all neighbors command to display BGP and TCP connection information for neighbor sessions specific to address families such as IPv4, IPv6, Network Service Access Point (NSAP), Virtual Private Network (VPN) v4, and VPNv6.
Examples
The following example shows output of the show bgp all neighbors command:
Router# show bgp all neighborsFor address family: IPv4 UnicastBGP neighbor is 172.16.232.53, remote AS 100, external linkMember of peer-group internal for session parametersBGP version 4, remote router ID 172.16.232.53BGP state = Established, up for 13:40:17Last read 00:00:09, hold time is 180, keepalive interval is 60 secondsMessage statistics:InQ depth is 0OutQ depth is 0Sent RcvdOpens: 3 3Notifications: 0 0Updates: 0 0Keepalives: 113 112Route Refresh: 0 0Total: 116 11Default minimum time between advertisement runs is 5 secondsConnections established 22; dropped 21Last reset 13:47:05, due to BGP Notification sent, hold time expiredExternal BGP neighbor may be up to 2 hops away.Connection state is ESTAB, I/O status: 1, unread input bytes: 0Local host: 3FFE:700:20:1::12, Local port: 55345Foreign host: 3FFE:700:20:1::11, Foreign port: 179Enqueued packets for retransmit: 0, input: 0 mis-ordered: 0 (0 bytes)Event Timers (current time is 0x1A0D543C):Timer Starts Wakeups NextRetrans 1218 5 0x0TimeWait 0 0 0x0AckHold 3327 3051 0x0SendWnd 0 0 0x0KeepAlive 0 0 0x0GiveUp 0 0 0x0PmtuAger 0 0 0x0DeadWait 0 0 0x0iss: 1805423033 snduna: 1805489354 sndnxt: 1805489354 sndwnd: 15531irs: 821333727 rcvnxt: 821591465 rcvwnd: 15547 delrcvwnd: 837SRTT: 300 ms, RTTO: 303 ms, RTV: 3 ms, KRTT: 0 msminRTT: 8 ms, maxRTT: 300 ms, ACK hold: 200 msFlags: higher precedence, nagleDatagrams (max data segment is 1420 bytes):Rcvd: 4252 (out of order: 0), with data: 3328, total data bytes: 257737Sent: 4445 (retransmit: 5), with data: 4445, total data bytes: 244128For address family: IPv6 UnicastFor address family: IPv4 MDTFor address family: VPNv4 UnicastFor address family: VPNv6 UnicastFor address family: IPv4 MulticastFor address family: IPv6 MulticastFor address family: NSAP UnicastTable 10 describes the significant fields shown in the display.
Related Commands
show bgp nsap
To display entries in the Border Gateway Protocol (BGP) routing table for the network service access point (NSAP) address family, use the show bgp nsap command in EXEC mode.
show bgp nsap [nsap-prefix]
Syntax in Cisco IOS Release 12.2(33)SRB
show bgp nsap unicast [nsap-prefix]
Syntax Description
Command Modes
User EXEC (>)
Privileged EXEC (#)Command History
Usage Guidelines
The show bgp nsap command provides output similar to the show ip bgp command, except that it is specific to the NSAP address family.
Examples
The following is sample output from the show bgp nsap command:
Router# show bgp nsapBGP table version is 6, local router ID is 10.1.57.11Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path*> 49.0101 49.0101.1111.1111.1111.1111.000 65101 i* i49.0202.2222 49.0202.3333.3333.3333.3333.00100 0 ?*> 49.0202.2222.2222.2222.2222.0032768 ?* i49.0202.3333 49.0202.3333.3333.3333.3333.00100 0 ?*> 49.0202.2222.2222.2222.2222.0032768 ?*> 49.0303 49.0303.4444.4444.4444.4444.000 65303 i* 49.0404 49.0303.4444.4444.4444.4444.000 65303 65404 i*>i 49.0404.9999.9999.9999.9999.00100 0 65404 iTable 11 describes the significant fields shown in the display.
The following is sample output from the show bgp nsap command, showing information for NSAP prefix 49.6005.1234.4567:
Router# show bgp nsap 49.6005.1234.4567BGP routing table entry for 49.6005.1234.4567, version 2Paths: (1 available, best #1)Not advertised to any peerLocal49.6005.1234.4567.5678.1111.2222.3333.00 from 0.0.0.0 (10.1.1.1)Origin IGP, localpref 100, weight 32768, valid, sourced, local, best
Note
In this example for Cisco IOS Release 12.2(33)SRB there is a new keyword, unicast, that is required. The output for the following command is the same as in the first example.
Router# show bgp nsap unicastshow bgp nsap community
To display routes that belong to specified network service access point (NSAP) Border Gateway Protocol (BGP) communities, use the show bgp nsap community command in EXEC mode.
show bgp nsap community [community-number] [exact-match | local-as | no-advertise | no-export]
Syntax in Cisco IOS Release 12.2(33)SRB
show bgp nsap unicast community [community-number] [exact-match | local-as | no-advertise | no-export]
Syntax Description
Command Modes
User EXEC (>)
Privileged EXEC (#)Command History
Usage Guidelines
The show bgp nsap community command provides output similar to the show ip bgp community command, except that it is specific to the NSAP address family.
Communities are set with the route-map and set community commands. Communities are sent using the neighbor send-community and neighbor route-map out commands. You must enter the numerical communities before the well-known communities. For example, the following string does not work:
Router> show bgp nsap community local-as 111:12345Use the following string instead:
Router> show bgp nsap community 111:12345 local-asExamples
The following is sample output from the show bgp nsap community command:
Router# show bgp nsap community no-exportBGP table version is 5, local router ID is 10.1.57.14Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path*> 49.0101.11 49.0101.2222.2222.2222.2222.000 101 iTable 12 describes the significant fields shown in the display.
In this example for Cisco IOS Release 12.2(33)SRB there is a new keyword, unicast, that is required. The output for the following command is the same as in the first example.
Router# show bgp nsap unicast community no-exportRelated Commands
show bgp nsap community-list
To display routes that are permitted by the Border Gateway Protocol (BGP) community list for network service access point (NSAP) prefixes, use the show bgp nsap community-list command in EXEC mode.
show bgp nsap community-list community-list-number [exact-match]
Syntax in Cisco IOS Release 12.2(33)SRB
show bgp nsap unicast community-list community-list-number [exact-match]
Syntax Description
community-list-number
Community list number in the range from 1 to 199.
exact-match
(Optional) Displays only routes that have an exact match.
unicast
Specifies NSAP unicast address prefixes.
Command Modes
User EXEC (>)
Privileged EXEC (#)Command History
Usage Guidelines
The show bgp nsap community-list command provides output similar to the show ip bgp community-list command, except that it is specific to the NSAP address family.
Examples
The following is sample output of the show bgp nsap community-list command:
Router# show bgp nsap community-list 1BGP table version is 6, local router ID is 10.0.22.33Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path*> 49.0a0a.bb 49.0a0a.bbbb.bbbb.bbbb.bbbb.000 606Table 13 describes the significant fields shown in the display.
In this example for Cisco IOS Release 12.2(33)SRB there is a new keyword, unicast, that is required. The output for the following command is the same as in the first example.
Router# show bgp nsap unicast community-list 1show bgp nsap dampened-paths
Effective with Cisco IOS Release 12.2(33)SRB, the show bgp nsap dampened-paths command is replaced by the show bgp nsap dampening command. See the show bgp nsap dampening command for more information.
To display network service access point (NSAP) address family Border Gateway Protocol (BGP) dampened routes in the BGP routing table, use the show bgp nsap dampened-paths command in EXEC mode.
show bgp nsap dampened-paths
Syntax Description
This command has no arguments or keywords.
Command Modes
User EXEC (>)
Privileged EXEC (#)Command History
Usage Guidelines
In Cisco IOS Release 12.2(33)SRB and later releases, the show bgp nsap dampened-paths command is replaced by the show bgp nsap dampening command. A keyword, dampened-paths, can be used with the new show bgp nsap dampened-paths command to display NSAP address family BGP dampened routes.
Examples
The following is sample output from the show bgp nsap dampened-paths command in privileged EXEC mode:
Router# show bgp nsap dampened-pathsBGP table version is 20, local router ID is 10.1.57.13Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork From Reuse Path*d 49.0404 10.2.4.2 00:25:50 65202 65404 iTable 14 describes the significant fields shown in the display.
Related Commands
show bgp nsap dampening
To display network service access point (NSAP) address family Border Gateway Protocol (BGP) dampened routes in the BGP routing table, use the show bgp nsap dampening command in user EXEC or privileged EXEC mode.
show bgp nsap unicast dampening {dampened-paths | flap-statistics [regexp regexp | quote-regexp regexp | filter-list access-list-number | nsap-prefix] | parameters}
Syntax Description
Command Modes
User EXEC (>)
Privileged EXEC (#)Command History
Examples
The following is sample output from the show bgp nsap dampened-paths command in privileged EXEC mode:
Router# show bgp nsap unicast dampening dampened-pathsBGP table version is 20, local router ID is 10.1.57.13Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork From Reuse Path*d 49.0404 10.2.4.2 00:25:50 65202 65404 iTable 15 describes the significant fields shown in the display.
The following is sample output from the show bgp nsap unicast dampening flap-statistics command:
Router# show bgp nsap unicast dampening flap-statisticsBGP table version is 20, local router ID is 10.1.57.13Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork From Flaps Duration Reuse Path*d 49.0404 10.2.4.2 3 00:09:45 00:23:40 65202 65404Table 16 describes the significant fields shown in the display.
Related Commands
show bgp nsap filter-list
To display routes in the Border Gateway Protocol (BGP) routing table for the network service access point (NSAP) address family that conform to a specified filter list, use the show bgp nsap filter-list command in privileged EXEC mode.
show bgp nsap filter-list access-list-number
Syntax in Cisco IOS Release 12.2(33)SRB
show bgp nsap unicast filter-list access-list-number
Syntax Description
access-list-number
Number of an autonomous system path access list. It can be a number from 1 to 199.
unicast
Specifies NSAP unicast address prefixes.
Command Modes
User EXEC (>)
Privileged EXEC (#)Command History
Examples
The following is sample output from the show bgp nsap filter-list command:
Router# show bgp nsap filter-list 1BGP table version is 3, local router ID is 10.0.11.33Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path*> 49.0b0b 49.0b0b.bbbb.bbbb.bbbb.bbbb.000 707 iTable 17 describes the significant fields shown in the display.
In this example for Cisco IOS Release 12.2(33)SRB there is a new keyword, unicast, that is required. The output for the following command is the same as in the first example.
Router# show bgp nsap unicast filter-list 1show bgp nsap flap-statistics
To display Border Gateway Protocol (BGP) flap statistics for network service access point (NSAP) prefixes, use the show bgp nsap flap-statistics command in EXEC mode.
show bgp nsap flap-statistics [regexp regexp | quote-regexp regexp | filter-list access-list-number | nsap-prefix]
Syntax in Cisco IOS Release 12.2(33)SRB
show bgp nsap unicast flap-statistics [regexp regexp | quote-regexp regexp | filter-list access-list-number | nsap-prefix]
Syntax Description
Command Modes
User EXEC (>)
Privileged EXEC (#)Command History
Usage Guidelines
The show bgp nsap flap-statistics command provides output similar to the show ip bgp flap-statistics command, except that it is specific to the NSAP address family.
If no arguments or keywords are specified, the router displays flap statistics for all NSAP prefix routes.
Examples
The following is sample output from the show bgp nsap flap-statistics command without arguments or keywords:
Router# show bgp nsap flap-statisticsBGP table version is 20, local router ID is 10.1.57.13Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork From Flaps Duration Reuse Path*d 49.0404 10.2.4.2 3 00:09:45 00:23:40 65202 65404Table 18 describes the significant fields shown in the display.
In this example for Cisco IOS Release 12.2(33)SRB there is a new keyword, unicast, that is required. The output for the following command is the same as in the first example.
Router# show bgp nsap unicast flap-statisticsRelated Commands
bgp dampening
Enables BGP route dampening or changes various BGP route dampening factors.
clear bgp nsap flap-statistics
Clears BGP flap statistics for NSAP prefix routes.
show bgp nsap inconsistent-as
To display Border Gateway Protocol (BGP) network service access point (NSAP) prefix routes with inconsistent originating autonomous systems, use the show bgp nsap inconsistent-as command in EXEC mode.
show bgp nsap inconsistent-as
Syntax in Cisco IOS Release 12.2(33)SRB
show bgp nsap unicast inconsistent-as
Syntax Description
Command Modes
User EXEC (>)
Privileged EXEC (#)Command History
Usage Guidelines
The show bgp nsap inconsistent-as command provides output similar to the show ip bgp inconsistent-as command, except that it is specific to the NSAP address family.
Use the show bgp nsap inconsistent-as command to discover any BGP routing table entries that contain inconsistent autonomous system path information. Inconsistent autonomous path information is useful for troubleshooting networks because it highlights a configuration error in the network.
Examples
The following is sample output from the show bgp nsap inconsistent-as command. In this example, the network prefix of 49.0a0a has two entries in the BGP routing table showing different originating paths. The originating path information should be the same in both entries.
Router# show bgp nsap inconsistent-asBGP table version is 3, local router ID is 10.1.57.17Status codes: s suppressed, d damped, h history, * valid, > best, i -internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path* 49.0a0a 49.0a0a.cccc.cccc.cccc.000 30 i*> 49.0a0a.aaaa.aaaa.aaaa.000 10 iTable 19 describes the significant fields shown in the display.
In this example for Cisco IOS Release 12.2(33)SRB there is a new keyword, unicast, that is required. The output for the following command is the same as in the first example.
Router# show bgp nsap unicast inconsistent-asshow bgp nsap neighbors
To display information about Border Gateway Protocol (BGP) network service access point (NSAP) prefix connections to neighbors, use the show bgp nsap neighbors command in EXEC mode.
show bgp nsap neighbors [ip-address [routes | flap-statistics | advertised-routes | paths regexp | dampened-routes]]
Syntax in Cisco IOS Release 12.2(33)SRB
show bgp nsap unicast neighbors [ip-address [routes | flap-statistics | advertised-routes | paths regexp | dampened-routes]]
Syntax Description
Command Modes
User EXEC (>)
Privileged EXEC (#)Command History
Usage Guidelines
The show bgp nsap neighbors command provides output similar to the show ip bgp neighbors command, except that it is specific to the NSAP address family.
Examples
The following is sample output from the show bgp nsap neighbors command:
Router# show bgp nsap neighbors 10.0.2.3BGP neighbor is 10.0.2.3, remote AS 64500, external linkBGP version 4, remote router ID 172.17.1.2BGP state = Established, up for 00:12:50Last read 00:00:50, hold time is 180, keepalive interval is 60 secondsNeighbor capabilities:Route refresh: advertised and received(new)Address family NSAP Unicast: advertised and receivedReceived 17 messages, 0 notifications, 0 in queueSent 17 messages, 0 notifications, 0 in queueRoute refresh request: received 0, sent 0Default minimum time between advertisement runs is 30 secondsFor address family: NSAP UnicastBGP table version 5, neighbor version 5Index 2, Offset 0, Mask 0x42 accepted prefixes consume 114 bytesPrefix advertised 2, suppressed 0, withdrawn 0Number of NLRIs in the update sent: max 1, min 0Connections established 1; dropped 0Last reset neverConnection state is ESTAB, I/O status: 1, unread input bytes: 0Local host: 10.0.2.2, Local port: 11000Foreign host: 10.0.2.3, Foreign port: 179Enqueued packets for retransmit: 0, input: 0 mis-ordered: 0 (0 bytes)Event Timers (current time is 0x115940):Timer Starts Wakeups NextRetrans 22 1 0x0TimeWait 0 0 0x0AckHold 19 7 0x0SendWnd 0 0 0x0KeepAlive 0 0 0x0GiveUp 0 0 0x0PmtuAger 0 0 0x0DeadWait 0 0 0x0iss: 2052706884 snduna: 2052707371 sndnxt: 2052707371 sndwnd: 15898irs: 1625021348 rcvnxt: 1625021835 rcvwnd: 15898 delrcvwnd: 486SRTT: 279 ms, RTTO: 446 ms, RTV: 167 ms, KRTT: 0 msminRTT: 0 ms, maxRTT: 300 ms, ACK hold: 200 msFlags: higher precedence, nagleDatagrams (max data segment is 1460 bytes):Rcvd: 30 (out of order: 0), with data: 19, total data bytes: 486Sent: 29 (retransmit: 1, fastretransmit: 0), with data: 20, total data bytes: 46Table 20 describes the significant fields shown in the display.
The following is sample output from the show bgp nsap neighbors command with the advertised-routes keyword:
Router# show bgp nsap neighbors 10.0.2.3 advertised-routesBGP table version is 5, local router ID is 172.17.1.2Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path*> 49.0101 49.0101.1111.1111.1111.1111.000 101 i*> 49.0202 49.0202.2222.2222.2222.2222.0032768 iThe following is sample output from the show bgp nsap neighbors command with the routes keyword:
Router# show bgp nsap neighbors 10.0.2.3 routesBGP table version is 5, local router ID is 172.17.1.2Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path*> 49.0303 49.0303.3333.3333.3333.3333.000 303 i*> 49.0404 49.0303.3333.3333.3333.3333.000 303 404 iTotal number of prefixes 2Table 21 describes the significant fields shown in the display.
The following is sample output from the show bgp nsap neighbors command with the paths keyword:
Router# show bgp nsap neighbors 10.0.3.3 paths ^101Address Refcount Metric Path0x62281590 1 0 101 i
Note
Table 22 describes the significant fields shown in the display.
The following sample output from the show bgp nsap neighbors command shows the NSAP prefix dampened routes for the neighbor at 10.0.2.2:
Router# show bgp nsap neighbors 10.0.2.2 dampened-routesBGP table version is 10, local router ID is 172.17.1.2Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork From Reuse Path*d 49.0101 10.0.2.2 00:25:50 202 101 iThe following sample output from the show bgp nsap neighbors command shows the NSAP prefix flap statistics for the neighbor at 10.0.2.2:
Router# show bgp nsap neighbors 10.0.2.2 flap-statisticsBGP table version is 10, local router ID is 10.1.57.14Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork From Flaps Duration Reuse Path*d 49.0101 10.0.2.2 3 00:07:00 00:24:50 202 101In this example for Cisco IOS Release 12.2(33)SRB there is a new keyword, unicast, that is required. The output for the following command is the same as in the first example.
Router# show bgp nsap unicast neighbors 10.0.2.3Related Commands
neighbor activate
Enables the exchange of information with a neighboring router.
show bgp nsap paths
To display all the Border Gateway Protocol (BGP) network service access point (NSAP) prefix paths in the database, use the show bgp nsap paths command in EXEC mode.
show bgp nsap paths [AS-path-regexp]
Syntax in Cisco IOS Release 12.2(33)SRB
show bgp nsap unicast paths [AS-path-regexp]
Syntax Description
AS-path-regexp
(Optional) Regular expression that is used to match the received paths in the database.
unicast
Specifies NSAP unicast address prefixes.
Command Modes
User EXEC (>)
Privileged EXEC (#)Command History
Usage Guidelines
The show bgp nsap paths command provides output similar to the show ip bgp paths command, except that it is specific to the NSAP address family.
Examples
The following is sample output from the show bgp nsap paths command without a specified regular expression:
Router# show bgp nsap pathsAddress Hash Refcount Metric Path0x622803FC 0 1 0 i0x62280364 1197 1 0 202 101 i0x62280448 1739 1 0 202 i0x622803B0 1941 1 0 404 iTable 23 describes the significant fields shown in the display.
In this example for Cisco IOS Release 12.2(33)SRB there is a new keyword, unicast, that is required. The output for the following command is the same as in the first example.
Router# show bgp nsap unicast pathsshow bgp nsap quote-regexp
To display Border Gateway Protocol (BGP) network service access point (NSAP) prefix routes matching the AS-path regular expression as a quoted string of characters, use the show bgp nsap quote-regexp command in privileged EXEC mode.
show bgp nsap quote-regexp as-path-regexp
Syntax in Cisco IOS Release 12.2(33)SRB
show bgp nsap unicast quote-regexp as-path-regexp
Syntax Description
as-path-regexp
Regular expression to match the BGP autonomous system paths. The regular expression is contained within quotes.
unicast
Specifies NSAP unicast address prefixes.
Command Modes
User EXEC (>)
Privileged EXEC (#)Command History
Usage Guidelines
The show bgp nsap quote-regexp command provides output similar to the show ip bgp quote-regexp command, except that it is specific to the NSAP address family.
Examples
The following is sample output from the show bgp nsap quote-regexp command that shows paths equal to 202:
Router# show bgp nsap quote-regexp "202"BGP table version is 10, local router ID is 10.1.57.14Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path*d 49.0101 49.0202.2222.2222.2222.2222.000 202 101 i*> 49.0202 49.0202.2222.2222.2222.2222.000 202 iTable 24 describes the significant fields shown in the display.
In this example for Cisco IOS Release 12.2(33)SRB there is a new keyword, unicast, that is required. The output for the following command is the same as in the first example.
Router# show bgp nsap unicast quote-regexp "202"Related Commands
show bgp nsap regexp
Displays NSAP prefix routes matching the AS-path regular expression.
show bgp nsap regexp
To display Border Gateway Protocol (BGP) network service access point (NSAP) prefix routes matching the AS-path regular expression, use the show bgp nsap regexp command in privileged EXEC mode.
show bgp nsap regexp AS-path-regexp
Syntax in Cisco IOS Release 12.2(33)SRB
show bgp nsap unicast regexp AS-path-regexp
Syntax Description
AS-path-regexp
Regular expression to match the BGP autonomous system paths.
unicast
Specifies NSAP unicast address prefixes.
Command Modes
User EXEC (>)
Privileged EXEC (#)Command History
Usage Guidelines
The show bgp nsap regexp command provides output similar to the show ip bgp regexp command, except that it is specific to the NSAP address family.
Examples
The following is sample output from the show bgp nsap regexp command that shows paths beginning with 202 or containing 101:
Router# show bgp nsap regexp ^202 101BGP table version is 10, local router ID is 10.1.57.14Status codes: s suppressed, d damped, h history, * valid, > best, i - internalOrigin codes: i - IGP, e - EGP, ? - incompleteNetwork Next Hop Metric LocPrf Weight Path*d 49.0101 49.0202.2222.2222.2222.2222.000 202 101 i
Note
Table 25 describes the significant fields shown in the display.
In this example for Cisco IOS Release 12.2(33)SRB there is a new keyword, unicast, that is required. The output for the following command is the same as in the first example.
Router# show bgp nsap unicast regexp ^202 101Related Commands
show bgp nsap quote-regexp
Displays BGP NSAP prefix routes matching the AS-path regular expression.
show bgp nsap summary
To display the status of all Border Gateway Protocol (BGP) network service access point (NSAP) prefix connections, use the show bgp nsap summary command in EXEC mode.
show bgp nsap summary
Syntax in Cisco IOS Release 12.2(33)SRB
show bgp nsap unicast summary
Syntax Description
Command Modes
User EXEC (>)
Privileged EXEC (#)Command History
Usage Guidelines
The show bgp nsap summary command provides output similar to the show ip bgp summary command, except that it is specific to the NSAP address family.
Examples
The following is sample output from the show bgp nsap summary command:
Router# show bgp nsap summaryBGP router identifier 10.2.4.2, local AS number 65202BGP table version is 26, main routing table version 265 network entries and 8 paths using 1141 bytes of memory6 BGP path attribute entries using 360 bytes of memory4 BGP AS-PATH entries using 96 bytes of memory0 BGP route-map cache entries using 0 bytes of memory0 BGP filter-list cache entries using 0 bytes of memoryDampening enabled. 0 history paths, 0 dampened pathsBGP activity 16/261 prefixes, 34/26 paths, scan interval 60 secsNeighbor V AS MsgRcvd MsgSent TblVer InQ OutQ Up/Down State/PfxRcd10.1.2.1 4 65101 1162 1162 26 0 0 18:17:07 110.2.3.3 4 65202 1183 1188 26 0 0 18:23:28 310.2.4.4 4 65303 1163 1187 26 0 0 18:23:14 2Table 26 describes the significant fields shown in the display.
.
In this example for Cisco IOS Release 12.2(33)SRB there is a new keyword, unicast, that is required. The output for the following command is the same as in the first example.
Router# show bgp nsap unicast summaryRelated Commands
