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Table Of Contents
MPLS Traffic Engineering (TE): Link and Node Protection, with RSVP Hellos Support
Bandwidth Protection Considerations
Using Backup Tunnels with Explicitly Signaled Bandwidth
Using Backup Tunnels Signaled with Zero Bandwidth
Related Features and Technologies
Supported Platforms and Interfaces
Supported Standards, MIBs, RFCs, and Drafts
Creating a Backup Tunnel to the Next Hop or to the Next-Next Hop
Assigning Backup Tunnels to a Protected Interface
Associating Backup-Bandwidth and Pool Type with a Backup Tunnel
Configuring an Interface for Fast Link and Node Failure Detection
Verifying That Fast ReRoute Is In Place
Enabling Fast ReRoute for all Tunnels
Creating an NHOP Backup Tunnel
Creating an NNHOP Backup Tunnel
Assigning Backup Tunnels to a Protected Interface
Associating Backup-Bandwidth and Pool Type with Backup Tunnels
Configuring RSVP Hello and POS Signals
clear ip rsvp hello instance counters
clear ip rsvp hello instance statistics
clear ip rsvp hello statistics
ip rsvp signalling hello (configuration)
ip rsvp signalling hello (interface)
ip rsvp signalling hello refresh interval
ip rsvp signalling hello refresh misses
ip rsvp signalling hello statistics
mpls traffic-eng fast-reroute timers
show ip rsvp hello instance detail
show ip rsvp hello instance summary
show mpls traffic tunnel backup
show mpls traffic-eng fast-reroute database
show mpls traffic-eng tunnels summary
tunnel mpls traffic-eng backup-bw
MPLS Traffic Engineering (TE): Link and Node Protection, with RSVP Hellos Support
Feature History
12.0(10)ST
Fast ReRoute Link Protection feature was introduced.
12.0(16)ST
Link Protection for Cisco Series 7200 and 7500 platforms was added.
12.0(22)S
Fast ReRoute enhancements were added.
12.0(23)S
The show mpls traffic-eng fast-reroute database command was revised.
12.0(24)S
Support for the Cisco 10720 Internet Router and the Cisco 12000 series router engine 3 was added.
12.2(18)SXD1
This feature was integrated into Cisco IOS Release 12.2(18)SX.
This document describes the Fast ReRoute (FRR) enhancements, including Node Protection, in Cisco IOS Release 12.0(24)S. Node Protection can be viewed as a superset of (that is, an enhancement to) FRR Link Protection. The document includes the following sections:
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Supported Platforms and Interfaces
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Feature Overview
Fast ReRoute (FRR) is a mechanism for protecting MPLS Traffic Engineering (TE) label-switched paths (LSPs) from link and node failures by locally repairing the LSPs at the point of failure, allowing data to continue to flow on them while their headend routers attempt to establish new end-to-end LSPs to replace them. FRR locally repairs the protected LSPs by rerouting them over backup tunnels that bypass failed links or nodes.
Backup tunnels that bypass only a single link of the LSP's path provide Link Protection. They protect LSPs if a link along their path fails by rerouting the LSP's traffic to the next hop (bypassing the failed link). These are referred to as next-hop (NHOP) backup tunnels because they terminate at the LSP's next hop beyond the point of failure. Figure 1 illustrates a next-hop backup tunnel.
Figure 1 Next-Hop Backup Tunnel
FRR provides Node Protection for LSPs. Backup tunnels that bypass next-hop nodes along LSP paths are called next-next-hop (NNH) backup tunnels because they terminate at the node following the next-hop node of the LSP paths, thereby bypassing the next-hop node. They protect LSPs if a node along their path fails by enabling the node upstream of the failure to reroute the LSPs and their traffic around the failed node to the next-next hop. FRR supports the use of RSVP Hellos to accelerate the detection of node failures. NNHOP backup tunnels also provide protection from link failures, because they bypass the failed link as well as the node.
Figure 2 illustrates a next-next hop backup tunnel.
Figure 2 Next-Next Hop Backup Tunnel
If an LSP is using a backup tunnel and something changes so that the LSP is no longer appropriate for the backup tunnel, the LSP is torn down. Such changes include the following:
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The Fast ReRoute enhancements include the following:
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Benefits
Node Protection
Backup tunnels that terminate at the next-next hop protect both the downstream link and node. This provides protection for link and node failures.
Multiple Backup Tunnels Can Protect the Same Interface
In addition to being required for Node Protection, this enhancement provides the following benefits:
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Bandwidth Protection
Rerouted LSPs not only have their packets delivered during a failure, but the quality of service can also be maintained.
Scalability
A backup tunnel can protect multiple LSPs. Furthermore, a backup tunnel can protect multiple interfaces. This is called many-to-one (N:1) protection. N:1 protection has significant scalability advantages over one-to-one (1:1) protection, where a separate backup tunnel must be used for each LSP needing protection. N:1 protection is not new with Node Protection; it existed with Link Protection.
Example of 1:1 protection: When 5,000 backup tunnels protect 5,000 LSPs, each router along the backup path must maintain state for an additional 5,000 tunnels.
Example of N:1 protection: When one backup tunnel protects 5,000 LSPs, each router along the backup path maintains one additional tunnel.
RSVP Hello
RSVP Hello allows a router to detect when its neighbor has gone down but its interface to that neighbor is still operational. When Layer 2 link protocols are unable to detect that the neighbor is unreachable, Hellos provide the detection mechanism; this allows the router to switch LSPs onto its backup tunnels and avoid packet loss.
Fast ReRoute Operation
This section illustrates and describes the following:
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Fast ReRoute Activation
Two mechanisms cause routers to switch LSPs onto their backup tunnels:
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When a router's link or neighboring node fails, the router often detects this failure by an interface down notification. On a GSR Packet Over SONET (POS) interface, this notification is very fast. When a router notices that an interface has gone down, it switches LPSs going out that interface onto their respective backup tunnels (if any).
RSVP Hellos can also be used to trigger Fast ReRoute. If RSVP Hellos are configured on an interface, messages are periodically sent to the neighboring router. If no response is received, Hellos declare that the neighbor is down. This causes any LSPs going out that interface to be switched to their respective backup tunnels.
Backup Tunnels Terminating at Different Destinations
Figure 3 illustrates an interface that has multiple backup tunnels terminating at different destinations and demonstrates why, in many topologies, support for Node Protection requires supporting multiple backup tunnels per protected interface.
Figure 3 Backup Tunnels that Terminate at Different Destinations
In this illustration, a single interface on R1 requires multiple backup tunnels. LSPs traverse the following routes:
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To provide protection if node R2 fails, two NNHOP backup tunnels are required: one terminating at R3 and one terminating at R4.
Backup Tunnels Terminating at the Same Destination
Figure 4 shows how backup tunnels terminating at the same location can be used for redundancy and load balancing. Redundancy and load balancing work for both NHOP and NNHOP backup tunnels.
Figure 4 Backup Tunnels that Terminate at the Same Destination
In this illustration, there are three routers: R1, R2, and R3. At R1, there are two NNHOP backup tunnels (T1 and T2) that go from R1 to R3 without traversing R2.
Redundancy—If R2 fails or the link from R1 to R2 fails, either backup tunnel can be used. If one backup tunnel is down, the other can be used. LSPs are assigned to backup tunnels when the LSPs are first established. This is done before a failure.
Load balancing—If neither backup tunnel has enough bandwidth to back up all LSPs, both tunnels can be used. Some LSPs will use one backup tunnel, other LSPs will use the other backup tunnel. The router decides the best way to fit the LSPs onto the backup tunnels.
Backup Tunnel Selection Procedure
When an LSP is signaled, each node along the LSP path that provides FRR protection for the LSP selects a backup tunnel for the LSP to use if either of the following events occurs:
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By having the node select the backup tunnel for an LSP before a failure occurs, the LSP can be rerouted onto the backup tunnel quickly if there is a failure.
For an LSP to be mapped to a backup tunnel, all of the following conditions must exist:
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Bandwidth Protection
A backup tunnel can be configured to protect two types of backup-bandwidth:
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Load-balancing on Limited-bandwidth Backup Tunnels
There may be more than one backup tunnel that has sufficient backup-bandwidth to protect a given LSP. In this case, the router chooses the one that has the least amount of backup-bandwidth available. This algorithm limits fragmentation, maintaining the largest amount of backup-bandwidth available.
Specifying limited backup bandwidth does not "guarantee" bandwidth protection if there is a link or node failure. For example, the set of NHOP and NNHOP backup tunnels that gets triggered when an interface fails may all share some link on the network topology, and this link may not have sufficient bandwidth to support all LSPs using this set of backup tunnels.
In Figure 5, both backup tunnels traverse the same links and hop. When the link between routers R1 and R4 fails, backup tunnels for primary tunnel 1 and primary tunnel 2 are triggered simultaneously. The two backup tunnels may share a link in the network.
Figure 5 Backup Tunnels Share a Link
In Figure 6, the backup tunnel for primary tunnel 1 may traverse routers R1-R2-R3-R4, and the backup tunnel for primary tunnel 2 may traverse routers R4-R2-R3-R1. In this case, the link R2-R3 may get overloaded if R1-R4 fails.
Figure 6 Overloaded Link
Load-balancing on Unlimited-bandwidth Backup Tunnels
More than one backup tunnel, each having unlimited backup-bandwidth, can protect a given interface. In this case, when choosing a backup tunnel for a given LSP, the router chooses the backup tunnel that has the least amount of backup-bandwidth in use. This algorithm evenly distributes the LSPs across backup tunnels based on LSP's bandwidth. If an LSP is requesting zero bandwidth, the router chooses the backup tunnel that is currently protecting the fewest LSPs.
Pool Type and Backup Tunnels
By default, a backup tunnel provides protection for LSPs that allocate from any pool (that is, global or sub-pool). However, a backup tunnel can be configured to protect only LSPs that use global-pool bandwidth, or only those that use sub-pool bandwidth.
Next-hop Versus Next-next Hop Backup Tunnels
More than one backup tunnel can protect a given LSP, where one backup tunnel terminates at the LSP's NNHOP, and the other terminates at the LSP's NHOP. In this case, the router chooses the backup tunnel that terminates at the NNHOP (that is, Fast ReRoute prefers NNHOP over NHOP backup tunnels).
Table 1 lists the tunnel selection priorities. The first choice is an NNHOP backup tunnel that acquires its bandwidth from a sub-pool or global-pool, and has limited bandwidth. If there is no such backup tunnel, the next choice (2) is a next-next hop backup tunnel that acquires a limited amount of bandwidth from any pool. The preferences go from 1 (best) to 8 (worst), where choice 3 is for an NNHOP backup tunnel with an unlimited amount of sub-pool or global-pool bandwidth.
Figure 7 shows an example of the backup tunnel selection procedure based on the designated amount of global-pool and sub-pool bandwidth currently available.
Figure 7 Choosing from Among Multiple Backup Tunnels
In this example, an LSP requires 20 units (kilobits per second) of sub-pool backup-bandwidth. The best backup tunnel is selected as follows:
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Promotion
After a backup tunnel has been chosen for an LSP, conditions may change that will cause us to reevaluate this choice. This reevaluation, if successful, is called promotion. Such conditions may include:
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For cases 1 and 2, above, the LSP's backup tunnel is evaluated immediately. Case 3 is addressed by periodically reevaluating LSP-to-backup tunnel mappings. By default, background reevaluation is performed every 5 minutes. This interval is configurable via the mpls traffic-eng fast-reroute timers command.
Bandwidth Protection Considerations
There are numerous ways in which bandwidth protection can be ensured. Table 2 describes the advantages and disadvantages of two methods.
Cisco implementation of FRR does not mandate a particular approach, and it provides the flexibility to use either of the above approaches. However, given a range of configuration choices, be sure that the choices constant with a particular bandwidth protection strategy.
The following sections describe some important issues in choosing an appropriate configuration:
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Using Backup Tunnels with Explicitly Signaled Bandwidth
There are two bandwidth parameters that must be set for a backup tunnel:
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To signal bandwidth requirements of a backup tunnel, configure the bandwidth of the backup tunnel by using the tunnel mpls traffic-eng bandwidth command.
To configure the backup-bandwidth of the backup tunnel, use the tunnel mpls traffic-eng backup-bw command.
The signaled bandwidth is used by the LSRs on the path of the backup tunnel to perform admission control and do appropriate bandwidth accounting.
The backup-bandwidth is used by the PLR (the head-end of the backup tunnel) to decide how much primary traffic can be rerouted to this backup tunnel if there is a failure.
Both parameters need to be set to ensure proper operation. The numerical value of the signaled bandwidth and the backup-bandwidth should be the same.
Protected Bandwidth Pools and the Bandwidth Pool from which the Backup Tunnel Reserves its Bandwidth
The tunnel mpls traffic-eng bandwidth command allows you to configure the following:
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The tunnel mpls traffic-eng backup-bw command allows you to specify the bandwidth pool to which the traffic must belong for the traffic to use this backup tunnel. Multiple pools are allowed.
There is no direct correspondence between the bandwidth pool that is protected and the bandwidth pool from which the bandwidth of the backup tunnel draws its bandwidth.
Example: In this example, assume the following:
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Bandwidth protection for 10 Kbps of sub-pool traffic on a given link can be achieved by any of the following combinations:
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tunnel mpls traffic-eng backup-bw sub-pool 10
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tunnel mpls traffic-eng backup-bw sub-pool 10 global-pool unlimited
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tunnel mpls traffic-eng backup-bw sub-pool 10 global-pool 30
Using Backup Tunnels Signaled with Zero Bandwidth
Frequently is desirable to use backup tunnels with zero signaled bandwidth, even when bandwidth protection is required. It may seem that if no bandwidth is explicitly reserved, no bandwidth guarantees can be provided. However, that is not necessarily true.
In the following situation:
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For each protected link AB with a max reservable sub-pool value of S, there may be a path from node A to node B such that the difference between max reservable global and max reservable sub-pool is at least S. If it is possible to find such paths for each link in the network, you can establish all the backup tunnels along such paths without any bandwidth reservations. If there is a single link failure, only one backup tunnel will use any link on its path. Since that path has at least S of available bandwidth (in the global pool), assuming that marking and scheduling is configured to classify the sub-pool traffic into a priority queue, the sub-pool bandwidth is guaranteed.
The above approach allows sharing of the global pool bandwidth between backup tunnels protecting independent link failures. The backup tunnels are expected to be used for only a short period of time after a failure (until the head-ends of affected LSPs reroute those LSPs to other paths with available sub-pool bandwidth). The probability of multiple unrelated link failures is very small (in the absence of node or SRLG failures, which result in multiple link failures). Therefore, it is reasonable to assume that link failures are in practice independent with high probability. This "independent failure assumption" in combination with backup tunnels signaled without explicit bandwidth reservation enables efficient bandwidth sharing that yields substantial bandwidth savings.
Backup tunnels protecting the sub-pool traffic do now draw bandwidth from any pool. Primary traffic using the global pool can use the entire global pool, and primary traffic using the sub-pool can use the entire sub-pool. Yet, sub-pool traffic has a complete bandwidth guarantee if there is a single link failure.
A similar approach can be used for node and SRLG protection. However, the decision of where to put the backup tunnels is more complicated because both node and SRLG failures effectively result in the simultaneous failure of several links. Therefore, the backup tunnels protecting traffic traversing all affected links cannot be computed independently of each other. The backup tunnels protecting groups of links corresponding to different failures can still be computed independently of each other, which results in similar bandwidth savings.
Signaled Bandwidth versus Backup-Bandwidth
Backup-bandwidth is used locally (by the router that is the head-end of the backup tunnel) to determine which, and how many, primary LSPs can be rerouted on a particular backup tunnel. The router ensures that the combined bandwidth requirement of these LSPs does not exceed the backup-bandwidth.
Therefore, even when the backup tunnel is signaled with zero bandwidth, the backup-bandwidth must be configured with the value corresponding to the actual bandwidth requirement of the traffic protected by this backup tunnel. Unlike the case when bandwidth requirements of the backup tunnels are explicitly signaled, the value of the signaled bandwidth (which is zero) is not the same value as the backup-bandwidth.
RSVP Hello Operation
RSVP Hello enables RSVP nodes to detect when a neighboring node is not reachable. This provides node-to-node failure detection. When such a failure is detected, it is handled in a similar manner as a link-layer communication failure.
RSVP Hello can be used by FRR when notification of link-layer failures is not available (for example, with Ethernet), or when the failure detection mechanisms provided by the link layer are not sufficient for the timely detection of node failures.
A node running Hello sends a Hello Request to a neighboring node every interval. If the receiving node is running Hello, it responds with Hello Ack. If four intervals pass and the sending node has not received an Ack or it receives a bad message, the sending node declares that the neighbor is down and notifies FRR.
There are two configurable parameters:
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Hello Instance
A Hello instance implements RSVP Hello for a given router interface address and remote IP address. A Hello instance is expensive because of the large number of Hello requests that are sent and the strains they put on the router resources. Therefore, create a Hello instance only when it is necessary and delete it when it is no longer needed.
There are two types of Hello instances:
Active Hello Instances
If a neighbor is unreachable when an LSP is ready to be fast rerouted, an active Hello instance is needed. Create an active Hello instance for each neighbor with at least one LSP in this state.
Active Hello instances periodically send Hello Request messages, and expect Hello Ack messages in response. If the expected Ack message is not received, the active Hello instance declares that the neighbor (remote IP address) is unreachable (lost). LSPs traversing that neighbor may be fast rerouted.
If there is a Hello instance with no LSPs for an unreachable neighbor, do not delete the Hello instance. Convert the active Hello instance to a passive Hello instance because there may be an active instance on the neighboring router that is sending Hello requests to this instance.
Passive Hello Instances
Passive Hello instances respond to Hello Request messages (sending Ack messages), but do not initiate Hello Request messages and do not cause LSPs to be fast rerouted. A router with multiple interfaces can run multiple Hello instances to different neighbors or to the same neighbor.
A passive Hello instance is created when a Hello Request is received from a neighbor with a source IP address/destination IP address pair in the IP header for which a Hello instance does not exist.
Delete passive instances if no Hello messages are received for this instance within 10 minutes.
Hello Commands
RSVP Hello comprises the following commands:
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RSVP Hello Configuration Commands
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RSVP Hello Statistics Commands
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RSVP Hello Show Commands
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RSVP Hello Debug Commands
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Restrictions
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Related Features and Technologies
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Related Documents
For IS-IS:
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For Link Protection:
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For MPLS Traffic Engineering:
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For OSPF:
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For RSVP:
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Supported Platforms and Interfaces
Supported Platforms
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Enhanced OSM POS modules
Enhanced FlexWAN with POS Port Adapters
WAN ports on the OSM-2+4GE-WAN+ module
WS-X6516
WS-X67xx
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4-port OC-3 POS
1-port OC-12 POS
1-port CHOC-12/DS3
1-port CHOC-12/ STM4 and OC3/ STM1
6-/12-port DS3
6-/12-port E3
6-port CT3
2-port CHOC-3/STM1–
1-port OC-48 POS
4-port OC-12 POS
8-/16-port OC-3 POS–
4-port OC-12c/STM-4c POS ISE
4-port CHOC-12 ISE
1-port OC-48c POS ISE
1-port CHOC-48 ISE
4-, 8-, and 16-port OC3c POS ISESupported Interfaces
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Determining Platform Support Through Cisco Feature Navigator
Cisco IOS software is packaged in feature sets that support specific platforms. To get updated information regarding platform support for this feature, access Cisco Feature Navigator. Cisco Feature Navigator dynamically updates the list of supported platforms as new platform support is added for the feature.
Cisco Feature Navigator is a web-based tool that enables you to determine which Cisco IOS software images support a specific set of features and which features are supported in a specific Cisco IOS image. You can search by feature or release. Under the release section, you can compare releases side by side to display both the features unique to each software release and the features in common.
To access Cisco Feature Navigator, you must have an account on Cisco.com. If you have forgotten or lost your account information, send a blank e-mail to cco-locksmith@cisco.com. An automatic check will verify that your e-mail address is registered with Cisco.com. If the check is successful, account details with a new random password will be e-mailed to you. Qualified users can establish an account on Cisco.com by following the directions at http://www.cisco.com/register.
Cisco Feature Navigator is updated regularly when major Cisco IOS software releases and technology releases occur. For the most current information, go to the Cisco Feature Navigator home page at the following URL:
Availability of Cisco IOS Software Images
Platform support for particular Cisco IOS software releases is dependent on the availability of the software images for those platforms. Software images for some platforms may be deferred, delayed, or changed without prior notice. For updated information about platform support and availability of software images for each Cisco IOS software release, refer to the online release notes or, if supported, Cisco Feature Navigator.
Supported Standards, MIBs, RFCs, and Drafts
Standards
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MIBs
No new or modified MIBs are supported by this feature.
To obtain lists of supported MIBs by platform and Cisco IOS release, and to download MIB modules, go to the Cisco MIB website on Cisco.com at the following URL:
http://www.cisco.com/public/sw-center/netmgmt/cmtk/mibs.shtml
RFCs and Drafts
This feature complies with draft-swallow-rsvp-bypass-label-03.txt.
Prerequisites
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Configuration Tasks
This section assumes that you want to add Fast ReRoute protection to a network in which MPLS TE LSPs are configured.
Before performing the configuration tasks, it is assumed that you have done the following tasks but you do not have to already have configured MPLS TE tunnels:
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To review how to configure MPLS TE tunnels, see the Cisco IOS Switching Services Configuration Guide, Release 12.2.
The following sections describe how to use FRR to protect LSPs in your network from link or node failures. Each task is identified as either required or optional.
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Enabling Fast ReRoute on LSPs
LSPs can use backup tunnels only if they have been configured as fast reroutable. To do this, enter the following commands, beginning in global configuration mode, at the headend of each LSP:
Creating a Backup Tunnel to the Next Hop or to the Next-Next Hop
To create a backup tunnel to the next hop or to the next-next hop, enter the following commands on the node that will be the headend of the backup tunnel (that is, the node whose downstream link or node may fail). The node on which you enter these commands must be a supported platform. See "Supported Platforms and Interfaces".
Creating a backup tunnel is basically no different from creating any other tunnel. None of the commands below is new.
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Assigning Backup Tunnels to a Protected Interface
To assign one or more backup tunnels to a protected interface, enter the following commands on the node that will be the headend of the backup tunnel (that is, the node whose downstream link or node may fail). The node on which you enter these commands must be a supported platform. See "Supported Platforms and Interfaces".
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Step 1
Router(config)# interface type slot/port
Moves configuration to the physical interface level, directing subsequent configuration commands to the specific physical interface identified by the type. The slot and port identify the slot and port being configured. The interface must be a supported interface. See "Supported Platforms and Interfaces".
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Router(config-if)# mpls traffic-eng backup-path tunnel tunnel-id
Allows LSPs going out this interface to use this backup tunnel if there is a link or node failure.
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Associating Backup-Bandwidth and Pool Type with a Backup Tunnel
To associate backup-bandwidth with a backup tunnel and designate the type of LSP that can use a backup tunnel, enter the following command:
Configuring an Interface for Fast Link and Node Failure Detection
To configure pos ais-shut, enter the following commands:
interface pos0/0pos ais-shutTo configure pos report lrdi on OS interfaces, enter the following commands:
interface pos0/0pos report lrdiVerifying That Fast ReRoute Is In Place
To ensure that Fast ReRoute can function, do the following:
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Fast ReRoute Configuration
To determine if Fast ReRoute has been configured correctly, do the following:
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Conditions that Must Exist for Backup Tunnels to be Operational
If you created LSPs and performed the required configuration tasks but do not have operational backup tunnels (that is, the backup tunnels are not up or the LSPs are not associated with those backup tunnels), verify that all the following conditions exist:
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On the router where the backup tunnels originate, enter the show mpls traffic-eng tunnels backup command. The command output will allow you to verify the following:
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If none of the above actions works, enable debug by entering the debug ip rsvp fast-reroute command and the debug mpls traffic-eng fast-reroute command on the router that is the headend of the backup tunnel. Then do the following:
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show mpls traffic-eng fast-reroute database command
Enter the clear ip rsvp hello instance counters command to verify the following:
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The following command output displays the LSPs that are protected:
Router# show mpls traffic-eng fast-reroute databaseTunnel head end item frr information:Protected Tunnel In-label intf/label FRR intf/label StatusTunne1l0 Tun pos5/0:Untagged Tu0:12304 readyPrefix item frr information:Prefix Tunnel In-label Out intf/label FRR intf/label Status10.0.0.11/32 Tu110 Tun hd pos5/0:Untagged Tu0:12304 readyLSP midpoint frr information:LSP identifier In-label Out intf/label FRR intf/label Status10.0.0.12 1 [459] 16 pos0/1:17 Tu2000:19 ready
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Router#show mpls forwarding-table 10.0.0.11 32 detailLocal Outgoing Prefix Bytes tag Outgoing Next Hoptag tag or VC or Tunnel Id switched interfaceTun hd Untagged 10.0.0.11/32 48 pos5/0 point2pointMAC/Encaps=4/8, MTU=1520, Tag Stack{22}48D18847 00016000No output feature configuredFast Reroute Protection via (Tu0, outgoing label 12304)
show mpls traffic tunnel backup command
The following show ip rsvp sender command output verifies that protection has been enabled.
Router# show mpls traffic-eng tunnel backupTunnel1000 Dest: 12.0.0.10 State: Upglb-pool cfg 100 inuse 0 num_lsps 0protects: POS0/0protects: POS0/1The command shows the following information for a given backup tunnel:
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show ip rsvp sender command
Following is sample output from the show ip rsvp sender detail command when the command is entered at the Point of Local Repair (PLR) before a failure. For a detailed explanation of the output, see the show ip rsvp sender command.
Router# show ip rsvp sender detailPATH:Tun Dest: 24.1.1.1 Tun ID: 1 Ext Tun ID: 23.1.1.1Tun Sender: 23.1.1.1, LSP ID: 126Path refreshes arriving on POS1/0 from PHOP 11.1.1.1Path refreshes being sent to NHOP 12.1.1.2 on POS1/1Session Attr::Setup Prio: 0, Holding Prio: 0Flags: Local Prot desired, Label Recording, SE StyleSession Name:tagsw4500-23_t1ERO:12.1.1.2 (Strict IPv4 Prefix, 8 bytes, /32)14.1.1.1 (Strict IPv4 Prefix, 8 bytes, /32)14.1.1.2 (Strict IPv4 Prefix, 8 bytes, /32)24.1.1.1 (Strict IPv4 Prefix, 8 bytes, /32)Traffic params - Rate: 0G bits/sec, Max. burst: 1K bytesFast-Reroute Backup info:Inbound FRR: Not activeOutbound FRR: Ready -- backup tunnel selectedBackup Tunnel: Tu2 (label 0)Bkup Sender Template:Tun Sender: 15.1.1.1, LSP ID: 126Bkup FilerSpec:Tun Sender: 15.1.1.1, LSP ID 126show ip rsvp reservation command
Following is sample output from the show ip rsvp reservation command entered at the head-end of a primary LSP. Entering the command at the head-end of the primary LSP shows, among other things, the status of FRR (that is, local protection) at each hop this LSP traverses. The per-hop information is collected in the Record Route Object (RRO) that travels with the Resv message from the tail to the head.
Router# sho ip rsvp res detReservation:Tun Dest: 24.1.1.1 Tun ID: 1 Ext Tun ID: 23.1.1.1Tun Sender: 23.1.1.1 LSP ID: 104Next Hop: 11.1.1.2 on POS1/0Label: 18 (outgoing)Reservation Style is Shared-Explicit, QoS Service is Controlled-LoadAverage Bitrate is 0 bits/sec, Maximum Burst is 1K bytesMin Policed Unit: 0 bytes, Max Pkt Size: 0 bytesRRO:12.1.1.1/32, Flags:0x1 (Local Prot Avail/to NHOP)Label subobject: Flags 0x1, C-Type 1, Label 1814.1.1.1/32, Flags:0x0 (Local Prot Avail/In Use/Has BW/to NHOP)Label subobject: Flags 0x1, C-Type 1, Label 1614.1.1.2/32, Flags:0x0 (No Local Protection)Label subobject: Flags 0x1, C-Type 1, Label 0Resv ID handle: CD000404.Policy: Accepted. Policy source(s): MPLS/TENotice the following about the primary LSP:
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The RRO display shows the following information, for each hop:
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Troubleshooting Tips
This section describes the following:
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LSPs Do Not Become Active; They Remain Ready
At a Point of Local Repair (PLR), LSPs transition from Ready to Active if one of the following events occurs:
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Primary Tunnel Does Not Select Backup Tunnel That is Up
If a backup tunnel is up, but it is not selected as a backup tunnel by the primary tunnel (LSP), enter the following commands for the backup tunnel:
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•
Note
Enhanced RSVP Commands
The following RSVP commands have been enhanced to display information that can be helpful when examining Fast ReRoute state or when troubleshooting Fast ReRoute:
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These commands show control plane state; they do not show data state. That is, they show information about RSVP messages (Path and Resv) used to signal LSPs. For information about the data packets being forwarded along LSPs, use the show mpls forwarding command.
RSVP Hello
The RSVP Hello feature enables RSVP nodes to detect when a neighboring node is not reachable. Use this feature when notification of link-layer failures is not available and unnumbered links are not used, or when the failure detection mechanisms provided by the link layer are not sufficient for timely node failure detection. Hello must be configured both globally on the router and on the specific interface to be operational.
The RSVP Hello commands are described briefly in the "RSVP Hello Operation" section and in more detail in the "Command Reference" section.
Hello Instances Have Not Been Created
If Hello instances have not been created, do the following:
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"No entry at index (error may self-correct, RRO may not yet have propagated from downstream node of interest)" Error Message is Printed at the Point of Local Repair
Fast ReRoute relies on a Record Route Object (RRO) in Resv messages arriving from downstream. Routers receiving Path messages with the SESSION_ATTRIBUTE bit indicating that the LSP is fast-reroutable should include an RRO in the corresponding Resv messages.
If an LSP is configured for Fast ReRoute, but the Resv arriving from a downstream router contains an incomplete RRO, the "No entry at index (error may self-correct, RRO may not yet have propagated from downstream node of interest)" message is printed. An incomplete RRO is one in which the NHOP or the NNHOP did not include an entry in the RRO.
This error typically means that backup tunnels to the NHOP or the NNHOP cannot be selected for this LSP because there is insufficient information about the NHOP or NNHOP due to the lack of an RRO entry.
Occasionally there are valid circumstances in which this situation occurs temporarily and the problem is self-corrected. If subsequent Resv messages arrive with a complete RRO, ignore the error message.
To determine whether the error has been corrected, view the RRO in Resv messages by entering the clear ip rsvp hello instance counters command. Use an output filter keyword to view only the LSP of interest.
"Couldn't get rsbs (error may self-correct when Resv arrives)" Error Message is Printed at the Point of Local Repair
The PLR cannot select a backup tunnel for an LSP until a Resv message has arrived from downstream.
When this error occurs, it typically means that something is truly wrong. For example, no reservation exists for this LSP. You can troubleshoot this problem by using the debug ip rsvp reservation command to enable debug.
Occasionally there are valid circumstances in which this error message occurs and there is no need for concern. One such circumstance is when an LSP experiences a change before any Resv message has arrived from downstream. Changes can cause a PLR to try to select a backup tunnel for an LSP, and the selection will fail (causing this error message) if no Resv message has arrived for this LSP.
Configuration Examples
This section provides the following configuration examples:
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The examples relate to the illustration shown in Figure 8.
Figure 8 Backup Tunnels
Enabling Fast ReRoute for all Tunnels
On router R1, enter interface configuration mode for each tunnel to be protected (Tunnel 1000 and Tunnel 2000). Enable these tunnels to use a backup tunnel in case of a link or node failure along their paths. Tunnel 1000 will use 10 units of bandwidth from the sub-pool; Tunnel 2000 will use 5 units of bandwidth from the global-pool.
interface Tunnel1000tunnel mpls traffic-eng fast-reroutetunnel mpls traffic-eng bandwidth sub-pool 10interface Tunnel2000tunnel mpls traffic-eng fast-reroutetunnel mpls traffic-eng bandwidth 5Creating an NHOP Backup Tunnel
On router R2, create an NHOP backup tunnel to R3. This backup tunnel should avoid using the link 12.1.1.2.
Router(config)# ip explicit-path name avoid-protected-linkRouter(cfg-ip-expl-path)# exclude-address 12.1.1.2Explicit Path name avoid-protected-link:____1: exclude-address 12.1.1.2Router(cfg-ip_expl-path)# endRouter(config)# interface Tunnel1Router(config-if)# ip unnumbered loopback0Router(config-if)# tunnel destination 3.3.3.3Router(config-if)# tunnel mode mpls traffic-eng0Router(config-if)# tunnel mpls traffic-eng path-option explicit avoid-protected-linkCreating an NNHOP Backup Tunnel
On router R2, create an NNHOP backup tunnel to R4. This backup tunnel should avoid R3.
Router(config)# ip explicit-path name avoid-protected-nodeRouter(cfg-ip-expl-path)# exclude-address 3.3.3.3Explicit Path name avoid-protected-node:____1: exclude-address 3.3.3.3Router(cfg-ip_expl-path)# endRouter(config)# interface Tunnel2Router(config-if)# ip unnumbered loopback0Router(config-if)# tunnel destination 4.4.4.4Router(config-if)# tunnel mode mpls traffic-eng0Router(config-if)# tunnel mpls traffic-eng path-option explicit avoid-protected-nodeAssigning Backup Tunnels to a Protected Interface
On router R2, associate both backup tunnels with interface POS5/0.
Router(config)# interface POS5/0Router(config-if)# mpls traffic-eng backup-path tunnel1Router(config-if)# mpls traffic-eng backup-path tunnel2Associating Backup-Bandwidth and Pool Type with Backup Tunnels
Backup tunnel 1 is to be used only by LSPs that take their bandwidth from the global pool. It does not provide bandwidth protection. Backup tunnel 2 is to be used only by LSPs that take their bandwidth from the sub-pool. Backup tunnel 2 provides bandwidth protection for up to 1000 units.
Router(config)# interface Tunnel1Router(config-if)# tunnel mpls traffic-eng backup-bw global-pool UnlimitedRouter(config)# interface Tunnel2Router(config-if)# tunnel mpls traffic-eng backup-bw sub-pool 1000Configuring RSVP Hello and POS Signals
Hello must be configured both globally on the router and on the specific interface on which you need Fast ReRoute protection. To configure Hello, use the following configuration commands:
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•
The following configuration commands are optional:
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•
•
For configuration examples, see the Hello command descriptions in the "Command Reference" section.
To configure POS signalling for detecting Fast ReRoute failures, enter pos report all or enter the following commands to request individual reports:
pos ais-shutpos report rdoolpos report laispos report lrdipos report paispos report prdipos report sd-berCommand Reference
This section documents new or modified commands. All other commands used with this feature are documented in the Cisco IOS Release 12.2 command reference publications.
New Commands—Backup Tunnels
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Modified Commands—Backup Tunnels
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New Commands—Hello
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Note
Figure 9 RSVP Configuration Example
clear ip rsvp hello instance counters
To clear (refresh) the values for Hello instance counters, use the clear ip rsvp hello instance counters command in global EXEC mode.
clear ip rsvp hello instance counters
Syntax Description
This command has no arguments or keywords.
Defaults
This command has no default behavior or values.
Command Modes
Global EXEC
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Examples
Following is sample output from the show ip rsvp hello instance detail command and then the clear ip rsvp hello instance counters command. Notice that the "Statistics" fields have been cleared to zero.
Router# show ip rsvp hello instance detailNeighbor 11.0.0.2 Source 11.0.0.1State: UP (for 2d18h)Type: PASSIVE (responding to requests)I/F: Et1/1LSPs protecting: 0Refresh Interval (msec) (used when ACTIVE)Configured: 100Statistics: (from 2398195 samples)Min: 100Max: 132Average: 100Waverage: 100 (Weight = 0.8)Current: 100Src_instance 0xA9F07C13, Dst_instance 0x9BBAA407Counters:Communication with neighbor lost:Num times: 0Reasons:Missed acks: 0Bad Src_Inst received: 0Bad Dst_Inst received: 0I/F went down: 0Neighbor disabled Hello: 0Msgs Received: 2398194Sent: 2398195Suppressed: 0Router# clear ip rsvp hello instance countersNeighbor 11.0.0.2 Source 11.0.0.1State: UP (for 2d18h)Type: PASSIVE (responding to requests)I/F: Et1/1LSPs protecting: 0Refresh Interval (msec) (used when ACTIVE)Configured: 100Statistics:Min: 0Max: 0Average: 0Waverage: 0Current: 0Src_instance 0xA9F07C13, Dst_instance 0x9BBAA407Counters:Communication with neighbor lost:Num times: 0Reasons:Missed acks: 0Bad Src_Inst received: 0Bad Dst_Inst received: 0I/F went down: 0Neighbor disabled Hello: 0Msgs Received: 2398194Sent: 2398195Suppressed: 0Related Commands
clear ip rsvp hello instance statistics
To clear Hello statistics for an instance, use the clear ip rsvp hello instance statistics command in global EXEC mode.
clear ip rsvp hello instance statistics
Syntax Description
This command has no arguments or keywords.
Defaults
This command has no default behavior or values.
Command Modes
Global EXEC
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Examples
This example shows output from the show ip rsvp hello statistics command and the values in those fields after you enter the clear ip rsvp hello instance statistics command.
Router# show ip rsvp hello statisticsStatus: EnabledPacket arrival queue:Wait times (msec)Current:0Average:0Weighted Average:0 (weight = 0.8)Max:4Current length: 0 (max:500)Number of samples taken: 2398525Router# clear ip rsvp hello instance statisticsStatus: EnabledPacket arrival queue:Wait times (msec)Current:0Average:0Weighted Average:0 (weight = 0.8)Max:0Current length: 0 (max:500)Number of samples taken: 0Related Commands
clear ip rsvp hello statistics
To globally clear Hello statistics, use the clear ip rsvp hello statistics command in global EXEC mode.
clear ip rsvp hello statistics
Syntax Description
This command has no arguments or keywords.
Defaults
This command has no default behavior or values.
Command Modes
Global EXEC
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Usage Guidelines
Use this command to remove all information about how long Hello packets have been in the Hello input queue.
Examples
Following is sample output from the show ip rsvp hello statistics command and the clear ip rsvp hello statistics command. Notice that the values in the "Packet arrival queue" fields have been cleared.
Router# show ip rsvp hello statisticsStatus: EnabledPacket arrival queue:Wait times (msec)Current:0Average:0Weighted Average:0 (weight = 0.8)Max:4Current length: 0 (max:500)Number of samples taken: 2398525Router# clear ip rsvp hello statisticsStatus: EnabledPacket arrival queue:Wait times (msec)Current:0Average:0Weighted Average:0 (weight = 0.8)Max:0Current length: 0 (max:500)Number of samples taken: 16Related Commands
Enables Hello statistics on the router.
Shows how long Hello packets have been in the Hello input queue.
debug ip rsvp hello
To verify that a Hello instance has been created, a Hello instance has been deleted, and that communication with a neighbor has been lost, use the debug ip rsvp hello command in global EXEC mode.
debug ip rsvp hello [stats]
Syntax Description
Defaults
This command has no default behavior or values.
Command Modes
Global EXEC
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Usage Guidelines
When you enter the debug ip rsvp hello command, RSVP signalling messages are shown, but RSVP HELLO messages are excluded because of the large number of HELLO messages that are sent.
Examples
Following is sample output from the debug ip rsvp hello command. The first portion of the output is for interface Se2/0 when Hello is created:
Router# debug ip rsvp hello00:22:03: RSVP-HELLO: rsvp_hello_inst_init: Initializing ACTIVE hello inst 12.0.0.2->12.0.0.300:22:03: RSVP-HELLO: rsvp_hello_create_instance_from_psb: Next hop Se2/0 is adjacent00:22:03: RSVP-HELLO: rsvp_hello_create_instance_from_psb: Create hello instance for 12.0.0.2->12.0.0.3 on Se2/0 (psb=61BC5F60)00:22:03: RSVP-HELLO: rsvp_hello_find_instance: psb_cnt=2 for hello inst 12.0.0.2->12.0.0.300:22:03: RSVP-HELLO: rsvp_hello_incoming_message: Neighbor 12.0.0.3 state changed to UP00:22:05: %LINK-3-UPDOWN: Interface Tunnel1, changed state to up00:22:06: %LINEPROTO-5-UPDOWN: Line protocol on Interface Tunnel1, changed state to uprsvp-3640-2(config-if)#rsvp-3640-2(config-if)#shutrsvp-3640-2(config-if)#The following output shows that Hello has been deleted:
00:25:19: RSVP-HELLO: rsvp_hello_path_delete: psb for hello inst 12.0.0.2->12.0.0.3 exited READY state (psb_cnt=1)00:25:19: RSVP-HELLO: rsvp_hello_path_delete: psb for hello inst 12.0.0.2->12.0.0.3 exited READY state (psb_cnt=0)00:25:19: RSVP-HELLO: rsvp_hello_path_delete: Last psb deleted, hello inst for 12.0.0.2->12.0.0.3 ACTIVE->PASSIVE00:25:19: RSVP-HELLO: rsvp_hello_path_delete: psb for hello inst 13.0.0.2->13.0.0.3 exited READY state (psb_cnt=0)00:25:19: RSVP-HELLO: rsvp_hello_path_delete: Last psb deleted, hello inst for 13.0.0.2->13.0.0.3 ACTIVE->PASSIVE00:25:21: %LINK-5-CHANGED: Interface Tunnel1, changed state to administratively down00:25:22: %LINEPROTO-5-UPDOWN: Line protocol on Interface Tunnel1,changed state to down00:05:51: RSVP-HELLO: Communication lost with 12.0.0.200:05:51: RSVP-HELLO: rsvp_hello_communication_lost: Neighbor 12.0.0.2 was reset (src_inst)Following is sample output from the debug ip rsvp hello stats command:
rsvp-3640-3(config)#ip rsvp sig hel statrsvp-3640-3(config)#endrsvp-3640-3#00:32:28: RSVP-HELLO: rsvp_hello_stats_init: Hello stats is being configuredRelated Commands
ip rsvp signalling hello (configuration)
To enable Hello globally on the router, use the ip rsvp signalling hello command in global configuration mode.
ip rsvp signalling hello
Syntax Description
This command has no arguments or keywords.
Defaults
This command has no default behavior or values.
Command Modes
Global configuration
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Usage Guidelines
To enable Hello globally on the router, you must enter this command. You also must enable Hello on the interface.
Examples
In the following example, Hello is enabled globally on the router:
Router(config-if)# ip rsvp signalling helloRelated Commands
Enables Hello on an interface where you need Fast ReRoute protection.
Enables Hello statistics on the router.
ip rsvp signalling hello (interface)
To enable Hello on an interface where you need Fast ReRoute protection, use the ip rsvp signalling hello command in interface configuration mode.
ip rsvp signalling hello
Syntax Description
This command has no arguments or keywords.
Defaults
This command has no default behavior or values.
Command Modes
Interface configuration
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Usage Guidelines
You must configure Hello globally on the router and on the specific interface.
Examples
In the following example, Hello is enabled on an interface:
Router(config-if)# ip rsvp signalling helloRelated Commands
ip rsvp signalling hello dscp
To set the Differentiated Services Code Point (DSCP) value that is in the IP header of the Hello message sent out from an interface, use the ip rsvp signalling hello dscp command in interface configuration mode. To disable this feature, use the no form of this command.
ip rsvp signalling hello dscp [num]
no ip rsvp signalling hello dscp
Syntax Description
Defaults
The default value is 0.
Command Modes
Interface configuration
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Usage Guidelines
If a link is congested, it is recommended that you set the DSCP to a value higher than zero (0) to reduce the likelihood that Hello messages will be dropped.
You configure the DSCP per interface, not per flow.
The DSCP applies to all RSVP flows installed on a specific interface. You can configure each interface independently for DSCP.
Examples
In the following example, Hello messages sent from this interface have a DSCP value of 48:
Router(config-if)# ip rsvp signalling hello dscp 48Related Commands
ip rsvp signalling hello refresh interval
To configure the Hello request interval, use the ip rsvp signalling hello refresh interval command in interface configuration mode.
ip rsvp signalling hello refresh interval num
Syntax Description
num
Frequency, in milliseconds, at which a node sends Hello messages to a neighbor. Valid values are from 10 to 30,000.
Defaults
200 milliseconds
Command Modes
Interface configuration
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Usage Guidelines
You can configure the Hello request interval on a per-neighbor basis. A node periodically generates a Hello message containing a HELLO REQUEST object for each neighbor whose status is being tracked. The frequency of those Hello messages is determined by the Hello interval.
Examples
In the following example, Hello requests are sent to a neighbor every 50 milliseconds:
Router(config-if)# ip rsvp signalling hello refresh interval 50Related Commands
Enables Hello on an interface where you need Fast ReRoute protection.
Shows how long Hello packets have been in the Hello input queue.
ip rsvp signalling hello refresh misses
To specify how many Hello acknowledgments a node can miss in a row before the node considers that communication with its neighbor is down, use the ip rsvp signalling hello refresh misses command in interface configuration mode.
ip rsvp signalling hello refresh misses num
Syntax Description
num
The number of sequential Hello acknowledgments that a node can miss. Valid values are from 4 to 10.
Defaults
The default is 4.
Command Modes
Interface configuration
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Usage Guidelines
Hello comprises a Hello message, a HELLO REQUEST object, and a HELLO ACK object. Each request is answered by an acknowledgment. If a link is very congested or has a very heavy load, set this number to a value higher than the default value to ensure that Hello does not falsely declare that a neighbor is down.
Examples
In the following example, if the node does not receive five Hello acknowledgments in a row, the node declares that its neighbor is down:
Router(config-if)# ip rsvp signalling hello refresh misses 5Related Commands
Enables Help on an interface.
Sets the DSCP value that is in Hello messages sent out from an interface.
ip rsvp signalling hello statistics
To enable Hello statistics on the router, use the ip rsvp signalling hello statistics command in global EXEC mode.
ip rsvp signalling hello statistics
Syntax Description
This command has no arguments or keywords.
Defaults
This command has no default behavior or values.
Command Modes
Global EXEC
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Examples
In the following example, Hello statistics are enabled on the router.
Router(config)# ip rsvp signalling hello statisticsRelated Commands
Clears Hello statistics for an instance.
Enables Hello globally on the router.
Shows how long Hello packets have been in the Hello input queue.
mpls traffic-eng backup-path
To assign one or more backup tunnels to a protected interface, use the mpls traffic-eng backup-path command in interface configuration mode.
mpls traffic-eng backup-path tunneltunnel-id
Syntax Description
Defaults
No backup tunnels are used if this interface goes down.
Command Modes
Interface configuration
Command History
Usage Guidelines
Enter this command on the interface to be protected (Link Protection), or on the interface whose downstream node is being protected (Node Protection). You can enter this command multiple times to select multiple backup tunnels for a given protected interface. An unlimited number of backup tunnels can be assigned to protect an interface. The only limitation is memory. By entering this command on a physical interface, LSPs using this interface (sending data out of this interface) can use the indicated backup tunnels if there is a link or node failure.
Examples
The following example assigns backup tunnel 34 to interface POS5/0:
Router(config)# interface pos5/0Router(config-if)# mpls traffic-eng backup-path tunnel34Related Commands
tunnel mpls traffic-eng fast-reroute
Enables an MPLS Traffic Engineering tunnel to use a backup tunnel if there is a link or node failure (provided that a backup tunnel exists).
mpls traffic-eng fast-reroute timers
To specify how often the router considers switching an LSP to a new (better) backup tunnel if additional backup-bandwidth becomes available, use the mpls traffic-eng fast-reroute timers command in global configuration mode. To disable this timer, set the frequency to zero or use the no form of this command.
mpls traffic-eng fast-reroute timers [frequency frequency]
no mpls traffic-eng fast-reroute timers
Syntax Description
Defaults
By default, the timer is running and is set to a frequency of every 300 seconds (5 minutes). If you enter no mpls traffic-eng fast-reroute timers, the router returns to this default behavior.
Command Modes
Global configuration
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Examples
In the following example, LSPs are scanned every 2 minutes (120 seconds) to see if they should be promoted to a better backup tunnel.
Router(config)# mpls traffic-eng fast-reroute timers frequency 120show ip rsvp hello
To show if Hello is enabled globally on the router and if Hello statistics are enabled, use the show ip rsvp hello command in global EXEC mode.
show ip rsvp hello
Syntax Description
This command has no arguments or keywords.
Defaults
This command has no default behavior or values.
Command Modes
Global EXEC
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Examples
The following is sample output from the show ip rsvp hello command:
Router# show ip rsvp helloState: EnabledStatistics: EnabledDefault State: DisabledDefault Statistics: DisabledTable 3 describes significant fields displayed in this example.
Related Commands
Enables Hello globally on the router.
Enables Hello statistics on the router.
Shows how long Hello packets have been in the Hello input queue.
show ip rsvp hello instance detail
To show detailed information about a Hello instance, use the show ip rsvp hello instance detail command in global EXEC mode.
show ip rsvp hello instance detail [filter destination ip-address]
Syntax Description
Defaults
This command has no default behavior or values.
Command Modes
Global EXEC
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Examples
The following is sample output from a show ip rsvp hello instance detail command:
Router# show ip rsvp hello instance detailNeighbor 11.0.0.2 Source 11.0.0.1State: UP (for 2d18h)Type: PASSIVE (responding to requests)I/F: Et1/1LSPs protecting: 0Refresh Interval (msec) (used when ACTIVE)Configured: 100Statistics: (from 2398195 samples)Min: 100Max: 132Average: 100Waverage: 100 (Weight = 0.8)Current: 100Src_instance 0xA9F07C13, Dst_instance 0x9BBAA407Counters:Communication with neighbor lost:Num times: 0Reasons:Missed acks: 0Bad Src_Inst received: 0Bad Dst_Inst received: 0I/F went down: 0Neighbor disabled Hello: 0Msgs Received: 2398194Sent: 2398195Suppressed: 0Table 4 describes the fields displayed in this example.
Related Commands
show ip rsvp hello instance summary
To show summary information about a Hello instance, use the show ip rsvp hello instance summary command in global EXEC mode.
show ip rsvp hello instance summary
Syntax Description
This command has no arguments or keywords.
Defaults
This command has no default behavior or values.
Command Modes
Global EXEC
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Examples
The following is sample output from the show ip rsvp hello instance summary command:
Router# show ip rsvp hello instance summaryI/F Neighbor Type State LostCntEt1/1 11.0.0.1 PASSIVE UP 0Se2/0 12.0.0.3 ACTIVE UP 0Et1/2 13.0.0.3 ACTIVE UP 0Table 5 describes the fields displayed in this example.
Related Commands
show ip rsvp hello statistics
To show how long Hello packets have been in the Hello input queue, use the show ip rsvp hello statistics command in global EXEC mode.
show ip rsvp hello statistics
Syntax Description
This command has no arguments or keywords.
Defaults
This command has no default behavior or values.
Command Modes
Global EXEC
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Usage Guidelines
You can use this command to determine if the Hello refresh interval is too small. If the interval is too small, communication may falsely be declared as lost.
Examples
The following is sample output from the show ip rsvp hello statistics command:
Router# show ip rsvp hello statisticsStatus: EnabledPacket arrival queue:Wait times (msec)Current:0Average:0Weighted Average:0 (weight = 0.8)Max:4Current length: 0 (max:500)Number of samples taken: 2398525Table 6 describes the fields displayed in this example.
Related Commands
Clears Hello statistics for an instance.
Globally clears Hello statistics.
Configures the Hello request interval.
Enables Hello statistics on the router.
show ip rsvp interface detail
To show the interface configuration for Hello, use the show ip rsvp interface detail command in global EXEC mode.
show ip rsvp interface detail [interface]
Syntax Description
Defaults
This command has no default behavior or values.
Command Modes
Global EXEC
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Examples
The following is sample output from the show ip rsvp interface detail command:
Router# show ip rsvp interface detail Et1/2Et1/2:Bandwidth:Curr allocated: 0G bits/secMax. allowed (total): 7500K bits/secMax. allowed (per flow): 7500K bits/secMax. allowed for LSP tunnels using sub-pools: 0G bits/secNeighbors:Using IP encap: 1. Using UDP encap: 0DSCP value used in RSVP msgs: 0x0Hello:State: EnabledRefresh Interval: 500Missed Acks: 4DSCP value used in HELLO msgs: 0Table 7 describes the fields displayed in this example.
Related Commands
show ip rsvp request
To display upstream reservation state (that is, information related to the Resv messages that this node will send upstream), use the show ip rsvp request command in EXEC mode.
show ip rsvp request [detail] {destination ipaddress | source ipaddress | dst-port pnum | src-port pnum}
Syntax Description
Defaults
This command has no default behavior or values.
Command Modes
EXEC
Command History
Usage Guidelines
When hundreds or thousands of tunnels exist and you are interested in only a few, it is useful to display output for only a single tunnel or a subset of tunnels. To request a limited display, enter the show ip rsvp request command with the appropriate keyword (which in this case is called an output filter): destination, source, dst-port, and src-port. You can enter any or all of the output filters, and you can enter them whether or not you specify the detail keyword.
Examples
Following is sample output from the show ip rsvp request detail command when the command is entered on the Merge Point (MP) before a failure and after a failure.
Note
Example 1: Command is entered on the MP before a failure
Router# show ip rsvp request detailRSVP Reservation. Tun Dest: 24.1.1.1 Tun Sender: 23.1.1.1,Tun ID: 1 LSP ID: 126Next Hop is 14.1.1.1 on POS0/1Label is 0Reservation Style is Shared-Explicit, QoS Service is Controlled-LoadAverage Bitrate is 0G bits/sec, Maximum Burst is 1K bytesRRO:EmptyExample 2: Command is entered on the MP after a failure
Router# show ip rsvp request detailRSVP Reservation. Tun Dest: 24.1.1.1 Tun Sender: 23.1.1.1,Tun ID: 1 LSP ID: 126Next Hop is 14.1.1.1 on POS0/1Label is 0Reservation Style is Shared-Explicit, QoS Service is Controlled-LoadAverage Bitrate is 0G bits/sec, Maximum Burst is 1K bytesRRO:EmptyFRR is in progress (we are Merge Point)RSVP Reservation. Tun Dest: 24.1.1.1 Tun Sender: 23.1.1.1,Tun ID: 1 LSP ID: 126Next Hop is 15.1.1.1 on POS0/1Label is 0Reservation Style is Shared-Explicit, QoS Service is Controlled-LoadAverage Bitrate is 0G bits/sec, Maximum Burst is 1K bytesRRO:EmptyFRR is in progress (we are Merge Point)Notice that after the failure, there are two entries for the rerouted LSP. Information referenced in the following explanation is highlighted.
The first entry continues to show the pre-failure information (i.e., Resv messages are being sent to 14.1.1.1 on Ethernet1). This state is for the Resv being sent upstream before the failure, in response to Path messages sent before the failure. This state may time out quickly, or it may continue to be refreshed for a few minutes if, for example, an upstream node is unaware of the failure.
The second entry shows the post-failure information (i.e., Resv messages are being sent to 15.1.1.1 on Ethernet2). This state is for the Resv messages being sent upstream after the failure (to the PLR), and will remain and be refreshed as long as the LSP is rerouted.
In this example, the MP is also the tail of the LSP. There is no RRO information because there are no nodes downstream.
show ip rsvp reservation
To display downstream reservation state information (that is, information related to the Resv message arriving from downstream), use the show ip rsvp reservation command in EXEC mode.
show ip rsvp reservation [detail] {destination ipaddress | source ipaddress | dst-port pnum | src-port pnum}
Syntax Description
Defaults
This command has no default behavior or values.
Command Modes
EXEC
Command History
Usage Guidelines
When hundreds or thousands of tunnels exist and you are interested in only a few, it is useful to display output for only a single tunnel or a subset of tunnels. To request a limited display, enter the show ip rsvp reservation command with the appropriate keyword (which in this case is called an output filter): destination, source, dst-port, and src-port. You can enter any or all of the output filters, and you can enter them whether or not you specify the detail keyword.
Examples
Following is sample output from the show ip rsvp reservation detail command when the command is entered on the Point of Local Repair (PLR) before a failure and after a failure.
Note
Example 1: Command is entered on the PLR before a failure
Router# show ip rsvp reservation detailRSVP Reservation. Tun Dest: 24.1.1.1 Tun Sender: 23.1.1.1,Tun ID: 1 LSP ID: 126Next Hop is 12.1.1.2 on POS1/2Label is 18Reservation Style is Shared-Explicit, QoS Service is Controlled-LoadAverage Bitrate is 0G bits/sec, Maximum Burst is 1K bytesRRO:14.1.1.1/32, Flags:0x0 (No Local Protection)Label record: Flags 0x1, ctype 1, incoming label 1814.1.1.2/32, Flags:0x0 (No Local Protection)Label record: Flags 0x1, ctype 1, incoming label 0Example 2: Command is entered on the PLR after a failure
Router# show ip rsvp reservation detailRSVP Reservation. Tun Dest: 24.1.1.1 Tun Sender: 23.1.1.1,Tun ID: 1 LSP ID: 126FRR is in progress: (we are PLR)Bkup Next Hop is 16.1.1.2 on POS1/1Label is 0Orig Next Hop was 12.1.1.2 on POS1/2Label was 18Reservation Style is Shared-Explicit, QoS Service is Controlled-LoadAverage Bitrate is 0G bits/sec, Maximum Burst is 1K bytesRRO:24.1.1.1/32, Flags:0x0 (No Local Protection)Label record: Flags 0x1, ctype 1, incoming label 0Notice the following (see highlighted text) in Examples 1 and 2:
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Related Commands
ip rsvp reservation
Enables a router to simulate RSVP Resv message reception from the sender.
Clears (refreshes) the values for Hello instance counters.
show ip rsvp sender
To display path state information (that is, information related to the Path messages arriving from upstream), and the state of Fast ReRoute for a given MPLS Traffic Engineering LSP, use the show ip rsvp sender command in EXEC mode.
show ip rsvp sender [detail] {destination ipaddress | source ipaddress | dst-port pnum | src-port pnum}
Syntax Description
Defaults
This command has no default behavior or values.
Command Modes
EXEC
Command History
Usage Guidelines
This command is very useful for determining the state of RSVP signalling both before and after an LSP has been fast rerouted. The command is most useful when you enter it at the Point of Local Repair (PLR) or at the Merge Point (MP).
When hundreds or thousands of tunnels exist and you are interested in only a few, it is useful to display output for only a single tunnel or a subset of tunnels. To request a limited display, enter the show ip rsvp sender command with the appropriate keyword (which in this case is called an output filter): destination, source, dst-port, and src-port. You can enter any or all of the output filters, and you can enter them whether or not you specify the detail keyword.
Examples
Following is sample output from the show ip rsvp sender detail command under the following circumstances:
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Note
Example 1: Command is entered at the PLR before a failure
The following is sample output from the show ip rsvp sender detail command when it is entered at the PLR before a failure:
Router# show ip rsvp sender detailPATH:Tun Dest: 24.1.1.1 Tun ID: 1 Ext Tun ID: 23.1.1.1Tun Sender: 23.1.1.1, LSP ID: 126Path refreshes arriving on POS1/0 from PHOP 11.1.1.1Path refreshes being sent to NHOP 12.1.1.2 on POS1/1Session Attr::Setup Prio: 0, Holding Prio: 0Flags: Local Prot desired, Label Recording, SE StyleSession Name:tagsw4500-23_t1ERO:12.1.1.2 (Strict IPv4 Prefix, 8 bytes, /32)14.1.1.1 (Strict IPv4 Prefix, 8 bytes, /32)14.1.1.2 (Strict IPv4 Prefix, 8 bytes, /32)24.1.1.1 (Strict IPv4 Prefix, 8 bytes, /32)Traffic params - Rate: 0G bits/sec, Max. burst: 1K bytesFast-Reroute Backup info:Inbound FRR: Not activeOutbound FRR: Ready -- backup tunnel selectedBackup Tunnel: Tu2 (label 0)Bkup Sender Template:Tun Sender: 15.1.1.1, LSP ID: 126Bkup FilerSpec:Tun Sender: 15.1.1.1, LSP ID 126Table 8 describes the significant fields.
Note
Example 2: Command is entered at the PLR after a failure
If the LSP begins actively using the backup tunnel and the command is entered at the PLR after a failure, the display changes as shown below.
Note
Router# show ip rsvp sender detailPATH:Tun Dest: 24.1.1.1 Tun ID: 1 Ext Tun ID: 23.1.1.1Tun Sender: 23.1.1.1, LSP ID: 126Path refreshes arriving on POS1/0 from PHOP 11.1.1.1Path refreshes being sent to NHOP 24.1.1.1 on Tunnel2Session Attr::Setup Prio: 0, Holding Prio: 0Flags: Local Prot desired, Label Recording, SE StyleSession Name:tagsw4500-23_t1ERO:24.1.1.1 (Strict IPv4 Prefix, 8 bytes, /32)24.1.1.1 (Strict IPv4 Prefix, 8 bytes, /32)Traffic params - Rate: 0G bits/sec, Max. burst: 1K bytesFast-Reroute Backup info:Inbound FRR: Not activeOutbound FRR: Active -- using backup tunnelBackup Tunnel: Tu2 (label 0)Bkup Sender Template:Tun Sender: 15.1.1.1, LSP ID: 126Bkup FilerSpec:Tun Sender: 15.1.1.1, LSP ID 126Orig Output I/F: Et2Orig Output ERO:12.1.1.2 (Strict IPv4 Prefix, 8 bytes, /32)14.1.1.1 (Strict IPv4 Prefix, 8 bytes, /32)14.1.1.2 (Strict IPv4 Prefix, 8 bytes, /32)24.1.1.1 (Strict IPv4 Prefix, 8 bytes, /32)Once an LSP is actively using a backup tunnel, the following changes occur:
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Example 3: Command is entered at the MP before a failure
If the same show ip rsvp sender command is entered at the Merge Point (the backup tunnel tail), the display changes from before to after the failure. Following is sample output before a failure:
Router# show ip rsvp sender detailPATH:Tun Dest: 24.1.1.1 Tun ID: 1 Ext Tun ID: 23.1.1.1Tun Sender: 23.1.1.1, LSP ID: 126Path refreshes arriving on POS0/0 from PHOP 14.1.1.1Session Attr::Setup Prio: 0, Holding Prio: 0Flags: Local Prot desired, Label Recording, SE StyleSession Name:tagsw4500-23_t1Traffic params - Rate: 0G bits/sec, Max. burst: 1K bytesFast-Reroute Backup info:Inbound FRR: Not activeOutbound FRR: No backup tunnel selectedExample 4: Command is entered at the MP after a failure
After a failure, the following changes occur:
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Following is sample output after a failure:
Router# show ip rsvp sender detailPATH:Tun Dest: 24.1.1.1 Tun ID: 1 Ext Tun ID: 23.1.1.1Tun Sender: 23.1.1.1, LSP ID: 126Path refreshes arriving on POS0/1 from PHOP 15.1.1.1 on Loopback0Session Attr::Setup Prio: 0, Holding Prio: 0Flags: Local Prot desired, Label Recording, SE StyleSession Name:tagsw4500-23_t1Traffic params - Rate: 0G bits/sec, Max. burst: 1K bytesFast-Reroute Backup info:Inbound FRR: ActiveOrig Input I/F: POS0/0Orig PHOP: 14.1.1.1Now using Bkup Filterspec w/ sender: 15.1.1.1 LSP ID: 126Outbound FRR: No backup tunnel selectedNotice the following changes, which are highlighted in the sample command output:
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Example 5: Command output shows all senders
In the following example, information about all senders is displayed.
Router# show ip rsvp senderTo From Pro DPort Sport Prev Hop I/F BPS Bytes24.1.1.1 23.1.1.1 0 1 59 11.1.1.1 Et1 0G 1K24.1.1.1 25.1.1.1 0 2 9 0G 1K24.1.1.1 23.1.1.1 0 3 12 11.1.1.1 Et1 0G 1K24.1.1.1 25.1.1.1 0 3 20 0G 1K26.1.1.1 25.1.1.1 0 0 23 0G 1K26.1.1.1 25.1.1.1 0 1 22 0G 1K26.1.1.1 25.1.1.1 0 1000 22 0G 1KTable 9 describes the fields displayed in this example.
Example 6: Command output only shows senders who have a specific destination
To only show information about senders who have a specific destination, specify the destination filter as shown below. In this example, the destination is 26.6.6.6.
Router# show ip rsvp sender destination 26.6.6.6To From Pro DPort Sport Prev Hop I/F BPS Bytes26.1.1.1 25.1.1.1 0 0 23 0G 1K26.1.1.1 25.1.1.1 0 1 22 0G 1K26.1.1.1 25.1.1.1 0 1000 22 0G 1KExample 7: Show more detail about a sender who has a specific destination
To show more detail about the sender whose destination is 1000 (as shown in Example 6), specify the command with the destination port filter.
Router# show ip rsvp sender detail dst-port 1000PATH:Tun Dest 26.1.1.1 Tun ID 1000 Ext Tun ID 25.1.1.1Tun Sender: 25.1.1.1, LSP ID: 22Path refreshes being sent to NHOP 12.1.1.2 on Ethernet2Session Attr::Setup Prio: 7, Holding Prio: 7Flags: SE StyleSession Name:tagsw4500-25_t1000ERO:12.1.1.2 (Strict IPv4 Prefix, 8 bytes, /32)26.1.1.1 (Strict IPv4 Prefix, 8 bytes, /32)Traffic params - Rate: 0G bits/sec, Max. burst: 1K bytesFast-Reroute Backup info:Inbound FRR: Not activeOutbound FRR: No backup tunnel selectedRelated Commands
ip rsvp sender
Enables a router to simulate RSVP Path message reception from the sender.
show mpls traffic tunnel backup
To display information about the backup tunnels that are currently configured, use the show mpls traffic tunnel backup command in EXEC mode.
show mpls traffic tunnel backup tunneltunnel-id
Syntax Description
Defaults
This command has no default behavior or values.
Command Modes
EXEC
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Examples
The following is sample output from the show mpls traffic tunnel backup command.
Router# show mpls traffic tunnel backup tunnel1000Tunnel1000 Dest: 12.0.0.9 State: Upany-pool cfg 100 inuse 0 num_lsps 0protects: ATM0.1Table 10 describes the fields displayed in this example.
Related Commands
Specifies what types of LSPs can use a backup tunnel, whether the backup tunnel should provide bandwidth protection, and if so, how much.
show mpls traffic-eng fast-reroute database
To display the contents of the Fast ReRoute database, use the show mpls traffic-eng fast-reroute database command in EXEC mode.
show mpls traffic-eng fast-reroute database
{network [mask | masklength]
| labels low label [-high label] |
interface ifname |
backup-interface ifname}]
[state {active | ready | partial | complete }]
[role {head | middle}]
[detail]Syntax Description
Defaults
This command has no default behavior or values.
Command Modes
EXEC
Command History
Usage Guidelines
A tunnel head end item is created and added to the FRR database for each TE tunnel that is protected by Fast ReRoute. The existence of the head end item indicates that the label rewrite stored in the LFIB is protected, and that any IP prefix that uses the tunnel as its next hop will be FRR protected. You can confirm this information for each individual prefix by using the show mpls forwarding-table detail command.
A prefix item is created and added to the FRR database for each prefix that has label information associated with it via TDP/LDP and is being routed over a protected TE tunnel.Those items correspond to unique label rewrites, which are FRR protrected and used by LFIB.
LSP midpoint items are created and added to the FRR database for LSPs that use the node as a transit, if their LSP output interface is protected by Fast ReRoute.
Examples
The following is sample output from the show mpls traffic-eng fast-reroute database command at a tunnel head link. (Prefix item and LSP midpoint information categories are empty in this first example because LDP has not been enabled. In the second example, shown after Table 11, LDP has been enabled).
Router# show mpls traffic-eng fast-reroute databaseTunnel head end item frr information:Protected Tunnel In-label Out intf/label FRR intf/label StatusTunne1l0 Tun hd PO5/0:Untagged Tu0:12304 readyPrefix item frr information:Prefix Tunnel In-label Out intf/label FRR intf/label StatusLSP midpoint frr information:LSP identifier In-label Out intf/label FRR intf/label StatusTable 11 describes the fields displayed in this example.
The following is sample output from the show mpls traffic-eng fast-reroute database command when LDP has been enabled.
Router# show mpls traffic-eng fast-reroute databaseTunnel head end item frr information:Protected Tunnel In-label Out intf/label FRR intf/label StatusTunne1l0 Tun hd PO5/0:Untagged Tu0:14814 readyPrefix item frr information:Prefix Tunnel In-label Out intf/label FRR intf/label Status10.0.7.1/32 Tu10 12317 PO5/0:Untagged Tu0:14814 ready10.0.4.1/32 Tu10 12318 PO5/0:Untagged Tu0:14814 ready10.0.0.52/30 Tu10 12319 PO5/0:Untagged Tu0:14814 ready10.0.0.48/30 Tu10 12320 PO5/0:Untagged Tu0:14814 ready10.0.0.36/30 Tu10 12321 PO5/0:Untagged Tu0:14814 ready10.0.0.32/30 Tu10 12322 PO5/0:Untagged Tu0:14814 ready10.0.0.28/30 Tu10 12323 PO5/0:Untagged Tu0:14814 readyLSP midpoint frr information:LSP identifier In-label Out intf/label FRR intf/label StatusThe following example shows output, at a midpoint link, from the show mpls traffic-eng fast-reroute database command with the labels argument specified:
Router# show mpls traffic-eng fast-reroute database labels 250 - 255Protected Tunnel In-label Out intf/label FRR intf/label StatusLSP midpoint frr information:LSP identifier In-label Out intf/label FRR intf/label Status10.110.0.10 229 [7334] 255 PO0/0:694 Tu4000:694 active10.110.0.10 228 [7332] 254 PO0/0:693 Tu4000:693 active10.110.0.10 227 [7331] 253 PO0/0:692 Tu4000:692 active10.110.0.10 226 [7334] 252 PO0/0:691 Tu4000:691 active10.110.0.10 225 [7333] 251 PO0/0:690 Tu4000:690 active10.110.0.10 224 [7329] 250 PO0/0:689 Tu4000:689 activeThe following example shows output, at a tunnel head link, from the show mpls traffic-eng fast-reroute database command with the detail argument specified:
Router# show mpls traffic-eng fast-reroute database 12.0.0.0. detailLFIB FRR Database Summary:Total Clusters: 2Total Groups: 2Total Items: 789Link 10:PO5/0 (Down, 1 group)Group 51:PO5/0->Tu4000 (Up, 779 members)Prefix 12.0.0.0/16, Tu313, activeInput label Tun hd, Output label PO0/0:773, FRR label Tu4000:773Prefix 12.0.0.0/16, Tu392, activeInput label Tun hd, Output label PO0/0:775, FRR label Tu4000:775Prefix 12.0.0.0/16, Tu111, activeInput label Tun hd, Output label PO0/0:16, FRR label Tu4000:16Prefix 12.0.0.0/16, Tu394, activeInput label Tun hd, Output label PO0/0:774, FRR label Tu4000:774Table 12 describes the fields displayed in this example.
Related Commands
show mpls traffic-eng fast-reroute log reroutes
Displays contents of the Fast ReRoute event log.
show mpls traffic-eng tunnels
To show information about tunnels, use the show mpls traffic-eng tunnels command in EXEC mode.
show mpls traffic-eng tunnels
[tunnel unit]
[destination address]
[source-id {num | ipaddress | ipaddress num}]
[role {all | head | middle | tail | remote}]
[{up | down}]
[name string]
[suboptimal constraints {none | current | max}]
[{[interface in phys_intf] [interface out phys_intf] | [interface phys_intf ]}]
[property {backup | fast-reroute}]
[brief | backup | protection]Syntax Description
Defaults
If you specify this command without any arguments or keywords, the command displays general information about each MPLS TE tunnel known to the router.
Command Modes
EXEC
Command History
Usage Guidelines
To select the tunnels for which information is displayed, use the tunnel, destination, source-id, role, up, down, name, suboptimal, interface and property keywords and options singly or combined.
To select the type of information displayed about the selected tunnels, use the brief, accounting, backup, or protection keywords.
Examples
The following is sample output from the show mpls traffic-eng tunnel brief command. It displays brief information about every MPLS TE tunnel known to the router.
Router# show mpls traffic-eng tunnels briefSignalling Summary:LSP Tunnels Process: runningRSVP Process: runningForwarding: enabledPeriodic reoptimization: every 3600 seconds, next in 1706 secondsTUNNEL NAME DESTINATION UP IF DOWN IF STATE/PROTRouter_t1 10.112.0.12 - PO4/0/1 up/upRouter_t2 10.112.0.12 - unknown up/downRouter_t3 10.112.0.12 - unknown admin-downRouter_t1000 10.110.0.10 - unknown up/downRouter_t2000 10.110.0.10 - PO4/0/1 up/upDisplayed 5 (of 5) heads, 0 (of 0) midpoints, 0 (of 0) tailsTable 13 describes the fields displayed in this example.
The following is sample output from the show mpls traffic-eng tunnels property backup-tunnel brief command. It displays brief information about all MPLS TE tunnels acting as Fast Reroute backup tunnels (property backup) for interfaces on the router.
Router# show mpls traffic-eng tunnels property backup briefSignalling Summary:LSP Tunnels Process: runningRSVP Process: runningForwarding: enabledPeriodic reoptimization: every 3600 seconds, next in 2231 secondsPeriodic FRR Promotion: every 300 seconds, next in 131 secondsPeriodic auto-bw collection: disabledTUNNEL NAME DESTINATION UP IF DOWN IF STATE/PROTRouter_t578 88.88.88.88 - PO1/0 up/upRouter_t5710 7.7.7.7 - unknown admin-downRouter_t5711 7.7.7.7 - PO1/1 up/upDisplayed 3 (of 9) heads, 0 (of 1) midpoints, 0 (of 0) tailsThe following is sample output from the show mpls traffic-eng tunnels backup command. This command selects every MPLS TE tunnel known to the router and displays information about the Fast ReRoute protection each selected tunnels provides for interfaces on this router; the command does not generate output for tunnels that do not provide Fast ReRoute protection of interfaces on this router.
Router# show mpls traffic-eng tunnels backupRouter_t578LSP Head, Tunnel578, Admin: up, Oper: upSrc 55.55.55.55, Dest 88.88.88.88, Instance 1Fast Reroute Backup Provided:Protected i/fs: PO1/0, PO1/1, PO3/3Protected lsps: 1Backup BW: any pool unlimited; inuse: 100 kbpsRouter_t5710LSP Head, Tunnel5710, Admin: admin-down, Oper: downSrc 55.55.55.55, Dest 7.7.7.7, Instance 0Fast Reroute Backup Provided:Protected i/fs: PO1/1Protected lsps: 0Backup BW: any pool unlimited; inuse: 0 kbpsRouter_t5711LSP Head, Tunnel5711, Admin: up, Oper: upSrc 55.55.55.55, Dest 7.7.7.7, Instance 1Fast Reroute Backup Provided:Protected i/fs: PO1/0Protected lsps: 2Backup BW: any pool unlimited; inuse: 6010 kbpsThe following is sample output from the show mpls traffic-eng tunnels property fast-reroute protection command. This command selects every MPLS TE tunnel known to the router that was signaled as a Fast ReRoute protected LSP (property fast-reroute) and displays information about the protection this router provides each selected tunnel.
Router# show mpls traffic-eng tunnels property fast-reroute protectionRouter_t1LSP Head, Tunnel1, Admin: up, Oper: upSrc 55.55.55.55, Dest 88.88.88.88, Instance 25Fast Reroute Protection: RequestedOutbound: FRR ReadyBackup Tu5711 to LSP nhopTu5711: out i/f: PO1/1, label: implicit-nullLSP signalling info:Original: out i/f: PO1/0, label: 12304, nhop: 10.1.1.7With FRR: out i/f: Tu5711, label: 12304LSP bw: 6000 kbps, Backup level: any unlimited, type: any poolRouter_t2LSP Head, Tunnel2, Admin: up, Oper: upSrc 55.55.55.55, Dest 88.88.88.88, Instance 2Fast Reroute Protection: RequestedOutbound: FRR ReadyBackup Tu578 to LSP nhopTu578: out i/f: PO1/0, label: 12306LSP signalling info:Original: out i/f: PO3/3, label: implicit-null, nhop: 10.3.3.8With FRR: out i/f: Tu578, label: implicit-nullLSP bw: 100 kbps, Backup level: any unlimited, type: any poolr9_t1LSP Midpoint, signalled, connection upSrc 9.9.9.9, Dest 88.88.88.88, Instance 2347Fast Reroute Protection: RequestedInbound: FRR InactiveLSP signalling info:Original: in i/f: PO1/2, label: 12304, phop: 10.205.0.9Outbound: FRR ReadyBackup Tu5711 to LSP nhopTu5711: out i/f: PO1/1, label: implicit-nullLSP signalling info:Original: out i/f: PO1/0, label: 12305, nhop: 10.1.1.7With FRR: out i/f: Tu5711, label: 12305LSP bw: 10 kbps, Backup level: any unlimited, type: any poolshow mpls traffic-eng tunnels summary
To show summary information about tunnels, use the show mpls traffic-eng tunnels summary command in EXEC mode.
show mpls traffic-eng tunnels summary
Syntax Description
This command has no arguments or keywords.
Defaults
This command has no default behavior or values.
Command Modes
EXEC
Command History
Examples
The following is sample output from the show mpls traffic-eng tunnels summary command.
Note
Router# show mpls traffic-eng tunnels summarySignalling Summary:LSP Tunnels Process: runningRSVP Process: runningForwarding: enabledHead: 4 interfaces, 3 active signalling attempts, 3 established5 activations, 2 deactivationsMidpoints: 1, Tails: 0Periodic reoptimization: every 3600 seconds, next in 2778 secondsPeriodic fastreroute: every 300 seconds, next in 168 secondsPeriodic auto-bw collection: every 300 seconds, next in 78 secondsTable 14 describes the fields displayed in this example.
Related Commands
Specifies how often the router considers switching an LSP to a new (better) backup tunnel if additional backup-bandwidth becomes available.
tunnel mpls traffic-eng backup-bw
To specify what types of LSPs can use a backup tunnel, whether the backup tunnel should provide bandwidth protection, and if so, how much, use the tunnel mpls traffic-eng backup-bw command in interface configuration mode.
tunnel mpls traffic-eng backup-bw {bandwidth | [sub-pool {bandwidth | Unlimited}] [global-pool {bandwidth | Unlimited}]}
Syntax Description
global-pool
Only LSPs using bandwidth from the global-pool can use the backup tunnel.
sub-pool
Only LSPs using bandwidth from the sub-pool can use the backup tunnel.
bandwidth
The amount of bandwidth this backup tunnel can protect. The router limits the LSPs that can use this backup tunnel so that the sum of the bandwidth of the LSPs does not exceed the specified amount of bandwidth. If there are multiple backup tunnels, the router will use the best-fit algorithm (see "Backup Tunnel Selection Procedure") to determine which backup tunnel to use.
Unlimited
Backup tunnel does not provide bandwidth protection. Any number of LSPs can use the backup tunnel, regardless of their bandwidth.
Defaults
If neither sub-pool nor global-pool is entered, it is assumed that any LSP (those using bandwidth from the sub-pool or global-pool) can use this backup tunnel.
Command Modes
Interface configuration mode, on the backup tunnel interface
Command History
12.0(22)S
This command was introduced.
12.2(18)SXD1
This command was integrated into Cisco IOS Release 12.2(18)SX.
Usage Guidelines
If both sub-pool and global-pool are specified, sub-pool must be specified first on the command line. For example, tunnel mpls traffic-eng backup-bw sub-pool 100 global-pool Unlimited is legal, but it is not legal to specify tunnel mpls traffic-eng backup-bw global-pool Unlimited sub-pool 100.
To limit both sub-pool and global pool LSPs, enter tunnel mpls traffic-eng backup-bw sub-pool bandwidth global-pool bandwidth.
If sub-pool is Unlimited, global-pool cannot also be Unlimited. Entering such a command (tunnel mpls traffic-eng backup-bw sub-pool Unlimited global-pool Unlimited) would be the same as entering nothing at all because it is the default behavior.
Examples
In the following example, backup tunnel 1 is to be used only by LSPs that take their bandwidth from the global pool. The backup tunnel does not provide bandwidth protection. Backup tunnel 2 is to be used only by LSPs that take their bandwidth from the sub-pool. Backup tunnel 2 provides bandwidth protection for up to 1000 units.
Router(config)# interface Tunnel1Router(config-if)# tunnel mpls traffic-eng backup-bw global-pool UnlimitedRouter(config-if)# endRouter(config)# interface Tunnel2Router(config-if)# tunnel mpls traffic-eng backup-bw sub-pool 1000Router(config-if)# end
Related Commands
Glossary
backup tunnel—An MPLS Traffic Engineering tunnel used to protect other (primary) tunnels' traffic when a link or node failure occurs.
bandwidth—The available traffic capacity of a link.
CEF—Cisco Express Forwarding. A means for accelerating the forwarding of packets within a router, by storing route lookup.
Cisco Express Forwarding—See CEF.
differentiated services code point—See DSCP.
DSCP—Differentiated Services Code Point. Six bits in the IP header, as defined by the IETF. These bits determine the class of service provided to the IP packet.
enterprise network—A large and diverse network connecting most major points in a company or other organization.
Fast ReRoute—Procedures that enable temporary routing around a failed link or node while a new LSP is being established at the head end.
flooding—Traffic passing techniques used by switches and bridges in which traffic received on an interface is sent out all the interfaces of that device except the interface on which the information was received originally.
global pool—The total bandwidth allocated to an MPLS Traffic Engineering link or node.
headend—The router that originates and maintains a given LSP. This is the first router in the LSP's path.
hop—Passage of a data packet between two network nodes (for example, between two routers).
instance—A Hello instance implements the RSVP Hello extensions for a given router interface address and remote IP address. Active Hello instances periodically send Hello Request messages, expecting Hello ACK messages in response. If the expected Ack message is not received, the active Hello instance declares that the neighbor (remote IP address) is unreachable (that is, it is lost). This can cause LSPs crossing this neighbor to be fast rerouted.
interface—A network connection.
intermediate nodes—Intermediate System-to-Intermediate System. Link-state hierarchical routing protocol that calls for intermediate system (IS) routers to exchange routing information based on a single metric to determine network topology.
link—A point-to-point connection between adjacent nodes. There can be more than one link between adjacent nodes. A network communications channel consisting of a circuit or transmission path and all related equipment between a sender and a receiver. Sometimes referred to as a line or a transmission link.
label-switched path—See LSP.
limited backup-bandwidth—Backup tunnels that provide bandwidth protection.
load balancing—A configuration technique that shifts traffic to an alternative link if a certain threshold is exceeded on the primary link. Load balancing is similar to redundancy in that if an event causes traffic to shift directions, alternative equipment must be present in the configuration. In load balancing, the alternative equipment is not necessarily redundant equipment that only operates in the event of a failure.
LSP—Label-switched path. A configured connection between two routers, in which label switching is used to carry the packets. The purpose of an LSP is to carry data packets.
merge point—The backup tunnel's tail.
MPLS—Multiprotocol Label Switching. Packet-forwarding technology, used in the network core, that applies data link layer labels to tell switching nodes how to forward data, resulting in faster and more scalable forwarding than network layer routing normally can do.
MPLS global label allocation—There is one label space for all interfaces in the router. For example, label 100 coming in one interface is treated the same as label 100 coming in a different interface.
next hop—The next downstream node along an LSP's path. Also called NHOP.
next-hop backup tunnel—See NHOP backup tunnel.
next-next hop—The node after the next downstream node along an LSP's path. Also called NNHOP.
next-next-hop backup tunnel—See NNHOP backup tunnel.
NHOP—Next hop. The next downstream node along an LSP's path.
NHOP backup tunnel—Next-hop backup tunnel. Backup tunnel terminating at the LSP's next hop beyond the point of failure, and originating at the hop immediately upstream of the point of failure. It bypasses a failed link, and is used to protect primary LSPs that were using this link before the failure.
NNHOP—Next-next hop. The node after the next downstream node along an LSP's path.
NNHOP backup tunnel—Next-next-hop backup tunnel. Backup tunnel terminating at the LSP's next-next hop beyond the point of failure, and originating at the hop immediately upstream of the point of failure. It bypasses a failed link and/or node, and is used to protect primary LSPs that were using this link or node before the failure.
node—Endpoint of a network connection or a junction common to two or more lines in a network. Nodes can be interconnected by links, and serve as control points in the network. Computers on a network, or any endpoint or a junction common to two or more lines in a network. Nodes can be processors, controllers, or workstations.
OSPF—Open Shortest Path First. A link-state hierarchical Interior Gateway Protocol routing algorithm, derived from the IS-IS protocol. OSPF features include least-cost routing, multipath routing, and load balancing.
primary LSP—The last LSP originally signaled over the protected interface before the failure. The LSP before the failure.
primary tunnel—Tunnel whose LSP may be fast rerouted if there is a failure. Backup tunnels cannot be primary tunnels.
promotion—Conditions, such as a new backup tunnel comes up, cause a reevaluation of a backup tunnel that was chosen for an LSP. If the reevaluation is successful, it is called a promotion.
protected interface—An interface that has one or more backup tunnels associated with it.
redundancy—The duplication of devices, services, or connections so that, in the event of a failure, the redundant devices, services, or connections can perform the work of those that failed.
RSVP—Resource Reservation Protocol. An IETF protocol used for signaling requests (setting up reservations) for Internet services by a customer before that customer is permitted to transmit data over that portion of the network.
scalability—An indicator showing how quickly some measure of resource usage increases as a network gets larger.
state—Information that a router must maintain about each LSP. The information is used for rerouting tunnels.
sub-pool—The more restrictive bandwidth in an MPLS Traffic Engineering link or node. The sub-pool is a portion of the link or node's overall global pool bandwidth.
tailend—The router upon which an LSP is terminated. This is the last router in the LSP's path.
topology—The physical arrangement of network nodes and media within an enterprise networking structure.
tunnel—Secure communications path between two peers, such as two routers.
unlimited backup-bandwidth—Backup tunnels that provide no bandwidth (best-effort) protection (that is, they provide best-effort protection).
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