Table Of Contents
dhcpd address through distribute-list out Commands
dhcpd address
dhcpd auto_config
dhcpd dns
dhcpd domain
dhcpd enable
dhcpd lease
dhcpd option
dhcpd ping_timeout
dhcpd update dns
dhcpd wins
dhcprelay enable
dhcprelay information trust-all
dhcprelay information trusted
dhcprelay server (global)
dhcprelay server (interface) (9.1(2) and later)
dhcprelay setroute
dhcprelay timeout
dialog
dir
disable
disable (cache)
disable service-settings
display
distance eigrp
distance (OSPFv3)
distance ospf (OSPFv2)
distribute-list in
distribute-list out
dhcpd address through distribute-list out Commands
dhcpd address
To define the IP address pool used by the DHCP server, use the dhcpd address command in global configuration mode. To remove an existing DHCP address pool, use the no form of this command.
dhcpd address IP_address1[-IP_address2] interface_name
no dhcpd address interface_name
Syntax Description
interface_name
|
Interface to which the address pool is assigned.
|
IP_address1
|
Start address of the DHCP address pool.
|
IP_address2
|
End address of the DHCP address pool.
|
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Global configuration
|
•
|
•
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
The address pool of an ASA DHCP server must be within the same subnet of the ASA interface on which it is enabled, and you must specify the associated ASA interface using interface_name.
The size of the address pool is limited to 256 addresses per pool on the ASA. If the address pool range is larger than 253 addresses, the netmask of the ASA interface cannot be a Class C address (for example, 255.255.255.0) and needs to be something larger, for example, 255.255.254.0.
DHCP clients must be physically connected to the subnet of the ASA DCHP server interface.
The dhcpd address command cannot use interface names with a "-" (dash) character because this character is interpreted as a range specifier instead of as part of the object name.
The no dhcpd address interface_name command removes the DHCP server address pool that you configured for the specified interface.
See the CLI configuration guide for information about how to implement the DHCP server feature in the ASA.
Examples
The following example shows how to configure an address pool and DNS server for the DHCP clients on the DMZ interface of the ASA:
hostname(config)# dhcpd address 10.0.1.100-10.0.1.108 dmz
hostname(config)# dhcpd dns 209.165.200.226
hostname(config)# dhcpd enable dmz
The following example shows how to configure a DHCP server on the inside interface. The dhcpd address command assigns a pool of 10 IP addresses to the DHCP server on that interface.
hostname(config)# dhcpd address 10.0.1.101-10.0.1.110 inside
hostname(config)# dhcpd dns 198.162.1.2 198.162.1.3
hostname(config)# dhcpd wins 198.162.1.4
hostname(config)# dhcpd lease 3000
hostname(config)# dhcpd ping_timeout 1000
hostname(config)# dhcpd domain example.com
hostname(config)# dhcpd enable inside
Related Commands
Command
|
Description
|
clear configure dhcpd
|
Removes all DHCP server settings.
|
dhcpd enable
|
Enables the DHCP server on the specified interface.
|
show dhcpd
|
Displays DHCP binding, statistical, or state information.
|
show running-config dhcpd
|
Displays the current DHCP server configuration.
|
dhcpd auto_config
To enable the ASA to automatically configure DNS, WINS and domain name values for the DHCP server based on the values obtained from an interface running a DHCP or PPPoE client, or from a VPN server, use the dhcpd auto_config command in global configuration mode. To discontinue the automatic configuration of DHCP parameters, use the no form of this command.
dhcpd auto_config client_if_name [[vpnclient-wins-override] interface if_name]
no dhcpd auto_config client_if_name [[vpnclient-wins-override] interface if_name]
Syntax Description
client_if_name
|
Specifies the interface running the DHCP client that supplies the DNS, WINS, and domain name parameters.
|
interface if_name
|
Specifies the interface to which the action will apply.
|
vpnclient-wins-override
|
Overrides the interface DHCP or PPPoE client WINS parameter with the vpnclient parameter.
|
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Global configuration
|
•
|
—
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
If you specify DNS, WINS, or domain name parameters using the CLI commands, then the CLI-configured parameters overwrite the parameters obtained by automatic configuration.
Examples
The following example shows how to configure DHCP on the inside interface. The dhcpd auto_config command is used to pass DNS, WINS, and domain information obtained from the DHCP client on the outside interface to the DHCP clients on the inside interface.
hostname(config)# dhcpd address 10.0.1.101-10.0.1.110 inside
hostname(config)# dhcpd auto_config outside
hostname(config)# dhcpd enable inside
Related Commands
Command
|
Description
|
clear configure dhcpd
|
Removes all DHCP server settings.
|
dhcpd enable
|
Enables the DHCP server on the specified interface.
|
show ip address dhcp server
|
Displays detailed information about the DHCP options provided by a DHCP server to an interface acting as a DHCP client.
|
show running-config dhcpd
|
Displays the current DHCP server configuration.
|
dhcpd dns
To define the DNS servers for DHCP clients, use the dhcpd dns command in global configuration mode. To clear defined servers, use the no form of this command.
dhcpd dns dnsip1 [dnsip2] [interface if_name]
no dhcpd dns dnsip1 [dnsip2] [interface if_name]
Syntax Description
dnsip1
|
Specifies the IP address of the primary DNS server for the DHCP client.
|
dnsip2
|
(Optional) Specifies the IP address of the alternate DNS server for the DHCP client.
|
interface if_name
|
Specifies the interface to which values entered to the server apply. If no interface is specified, values are applied to all servers.
|
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Global configuration
|
•
|
•
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
The dhcpd dns command lets you specify the IP address or addresses of the DNS server(s) for the DHCP client. You can specify two DNS servers. The no dhcpd dns command lets you remove the DNS IP address(es) from the configuration.
Examples
The following example shows how to configure an address pool and DNS server for the DHCP clients on the DMZ interface of the ASA.
hostname(config)# dhcpd address 10.0.1.100-10.0.1.108 dmz
hostname(config)# dhcpd dns 192.168.1.2
hostname(config)# dhcpd enable dmz
Related Commands
Command
|
Description
|
clear configure dhcpd
|
Removes all DHCP server settings.
|
dhcpd address
|
Specifies the address pool used by the DHCP server on the specified interface.
|
dhcpd enable
|
Enables the DHCP server on the specified interface.
|
dhcpd wins
|
Defines the WINS servers for DHCP clients.
|
show running-config dhcpd
|
Displays the current DHCP server configuration.
|
dhcpd domain
To define the DNS domain name for DHCP clients, use the dhcpd domain command in global configuration mode. To clear the DNS domain name, use the no form of this command.
dhcpd domain domain_name [interface if_name]
no dhcpd domain [domain_name] [interface if_name]
Syntax Description
domain_name
|
Specifies the DNS domain name (example.com).
|
interface if_name
|
Specifies the interface to which values entered to the server apply. If no interface is specified, values are applied to all servers.
|
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Global configuration
|
•
|
•
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
The dhcpd domain command lets you specify the DNS domain name for the DHCP client. The no dhcpd domain command lets you remove the DNS domain server from the configuration.
Examples
The following example shows how to configure the domain name supplied to DHCP clients by the DHCP server on the ASA:
hostname(config)# dhcpd address 10.0.1.101-10.0.1.110 inside
hostname(config)# dhcpd dns 198.162.1.2 198.162.1.3
hostname(config)# dhcpd wins 198.162.1.4
hostname(config)# dhcpd lease 3000
hostname(config)# dhcpd ping_timeout 1000
hostname(config)# dhcpd domain example.com
hostname(config)# dhcpd enable inside
Related Commands
Command
|
Description
|
clear configure dhcpd
|
Removes all DHCP server settings.
|
show running-config dhcpd
|
Displays the current DHCP server configuration.
|
dhcpd enable
To enable the DHCP server, use the dhcpd enable command in global configuration mode. To disable the DHCP server, use the no form of this command.
dhcpd enable interface
no dhcpd enable interface
Syntax Description
interface
|
Specifies the interface on which to enable the DHCP server.
|
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Global configuration
|
•
|
•
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
The DHCP server provides network configuration parameters to DHCP clients. Support for the DHCP server within the ASA means that the ASA can use DHCP to configure connected clients. The dhcpd enable interface command lets you enable the DHCP daemon to listen for the DHCP client requests on the DHCP-enabled interface. The no dhcpd enable command disables the DHCP server feature on the specified interface.
Note
For multiple context mode, you cannot enable the DHCP server on an interface that is used by more than one context (a shared VLAN).
When the ASA responds to a DHCP client request, it uses the IP address and subnet mask of the interface at which the request was received as the IP address and subnet mask of the default gateway in the response.
Note
The ASA DHCP server daemon does not support clients that are not directly connected to an ASA interface.
See the CLI configuration guide for information about how to implement the DHCP server feature in the ASA.
Examples
The following example shows how to enable the DHCP server on the inside interface:
hostname(config)# dhcpd address 10.0.1.101-10.0.1.110 inside
hostname(config)# dhcpd dns 198.162.1.2 198.162.1.3
hostname(config)# dhcpd wins 198.162.1.4
hostname(config)# dhcpd lease 3000
hostname(config)# dhcpd ping_timeout 1000
hostname(config)# dhcpd domain example.com
hostname(config)# dhcpd enable inside
Related Commands
Command
|
Description
|
debug dhcpd
|
Displays debugging information for the DHCP server.
|
dhcpd address
|
Specifies the address pool used by the DHCP server on the specified interface.
|
show dhcpd
|
Displays DHCP binding, statistical, or state information.
|
show running-config dhcpd
|
Displays the current DHCP server configuration.
|
dhcpd lease
To specify the DHCP lease length, use the dhcpd lease command in global configuration mode. To restore the default value for the lease, use the no form of this command.
dhcpd lease lease_length [interface if_name]
no dhcpd lease [lease_length] [interface if_name]
Syntax Description
interface if_name
|
Specifies the interface to which values entered to the server apply. If no interface is specified, values are applied to all servers.
|
lease_length
|
Specifies the length of the IP address lease, in seconds, granted to the DHCP client from the DHCP server. Valid values are from 300 to 1048575 seconds.
|
Defaults
The default lease_length is 3600 seconds.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Global configuration
|
•
|
•
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
The dhcpd lease command lets you specify the length of the lease, in seconds, that is granted to the DHCP client. This lease indicates how long the DHCP client can use the assigned IP address that the DHCP server granted.
The no dhcpd lease command lets you remove the lease length that you specified from the configuration and replaces this value with the default value of 3600 seconds.
Examples
The following example shows how to specify the length of the lease of DHCP information for DHCP clients:
hostname(config)# dhcpd address 10.0.1.101-10.0.1.110 inside
hostname(config)# dhcpd dns 198.162.1.2 198.162.1.3
hostname(config)# dhcpd wins 198.162.1.4
hostname(config)# dhcpd lease 3000
hostname(config)# dhcpd ping_timeout 1000
hostname(config)# dhcpd domain example.com
hostname(config)# dhcpd enable inside
Related Commands
Command
|
Description
|
clear configure dhcpd
|
Removes all DHCP server settings.
|
show running-config dhcpd
|
Displays the current DHCP server configuration.
|
dhcpd option
To configure DHCP options, use the dhcpd option command in global configuration mode. To clear the option, use the no form of this command.
dhcpd option code {ascii string} | {ip IP_address [IP_address]} | {hex hex_string} [interface
if_name]
no dhcpd option code [interface if_name]
Syntax Description
ascii string
|
Specifies that the option parameter is an ASCII character string without spaces.
|
code
|
Specifies anumber representing the DHCP option being set. Valid values are 0 to 255 with several exceptions. See the Usage Guidelines section for the list of DHCP option codes that are not supported.
|
hex hex_string
|
Specifies that the option parameter is a hexadecimal string with an even number of digits and no spaces. You do not need to use a 0x prefix.
|
interface if_name
|
Specifies the interface to which values entered to the server apply. If no interface is specified, values are applied to all servers.
|
ip
|
Specifies that the option parameter is an IP address. You can specify a maximum of two IP addresses with the ip keyword.
|
IP_address
|
Specifies a dotted-decimal IP address.
|
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Global configuration
|
•
|
•
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
You can use the dhcpd option command to provide TFTP server information to Cisco IP Phones and routers.
When a DHCP option request arrives at the ASA DHCP server, the ASA places the value or values that are specified by the dhcpd option command in the response to the client.
The dhcpd option 66 and dhcpd option 150 commands specify TFTP servers that Cisco IP Phones and routers can use to download configuration files. Use these commands as follows:
•
dhcpd option 66 ascii string, where string is either the IP address or hostname of the TFTP server. Only one TFTP server can be specified for option 66.
•
dhcpd option 150 ip IP_address [IP_address], where IP_address is the IP address of the TFTP server. You can specify a maximum of two IP addresses for option 150.
Note
The dhcpd option 66 command only takes an ascii parameter, and the dhcpd option 150 only takes an ip parameter.
Use the following guidelines when specifying an IP address for the dhcpd option 66 | 150 commands:
•
If the TFTP server is located on the DHCP server interface, use the local IP address of the TFTP server.
•
If the TFTP server is located on a less secure interface than the DHCP server interface, then general outbound rules apply. Create a group of NAT, global, and access list entries for the DHCP clients, and use the actual IP address of the TFTP server.
•
If the TFTP server is located on a more secure interface, then general inbound rules apply. Create a group of static and access list statements for the TFTP server and use the global IP address of the TFTP server.
For information about other DHCP options, see RFC 2132.
Note
The ASA does not verify that the option type and value that you provide match the expected type and value for the option code as defined in RFC 2132. For example, you can enter the dhcpd option 46 ascii hello command, and the ASA accepts the configuration although option 46 is defined in RFC 2132 as a single-digit, hexadecimal value.
You cannot configure the following DHCP options with the dhcpd option command:
Option Code
|
Description
|
0
|
DHCPOPT_PAD
|
1
|
HCPOPT_SUBNET_MASK
|
12
|
DHCPOPT_HOST_NAME
|
50
|
DHCPOPT_REQUESTED_ADDRESS
|
51
|
DHCPOPT_LEASE_TIME
|
52
|
DHCPOPT_OPTION_OVERLOAD
|
53
|
DHCPOPT_MESSAGE_TYPE
|
54
|
DHCPOPT_SERVER_IDENTIFIER
|
58
|
DHCPOPT_RENEWAL_TIME
|
59
|
DHCPOPT_REBINDING_TIME
|
61
|
DHCPOPT_CLIENT_IDENTIFIER
|
67
|
DHCPOPT_BOOT_FILE_NAME
|
82
|
DHCPOPT_RELAY_INFORMATION
|
255
|
DHCPOPT_END
|
Examples
The following example shows how to specify a TFTP server for DHCP option 66:
hostname(config)# dhcpd option 66 ascii MyTftpServer
Related Commands
Command
|
Description
|
clear configure dhcpd
|
Removes all DHCP server settings.
|
show running-config dhcpd
|
Displays the current DHCP server configuration.
|
dhcpd ping_timeout
To change the default timeout for DHCP ping, use the dhcpd ping_timeout command in global configuration mode. To return to the default value, use the no form of this command.
dhcpd ping_timeout number [interface if_name]
no dhcpd ping_timeout [interface if_name]
Syntax Description
interface if_name
|
Specifies the interface to which values entered to the server apply. If no interface is specified, values are applied to all servers.
|
number
|
The timeout value of the ping, in milliseconds. The minimum value is 10, the maximum is 10000. The default is 50.
|
Defaults
The default number of milliseconds for number is 50.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Global configuration
|
•
|
•
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
To avoid address conflicts, the DHCP server sends two ICMP ping packets to an address before assigning that address to a DHCP client. The ASA waits for both ICMP ping packets to time out before assigning an IP address to a DHCP client. For example, if the default value is used, the ASA waits for 1500 milliseconds (750 milliseconds for each ICMP ping packet) before assigning an IP address.
A long ping timeout value can adversely affect the performance of the DHCP server.
Examples
The following example shows how to use the dhcpd ping_timeout command to change the ping timeout value for the DHCP server:
hostname(config)# dhcpd address 10.0.1.101-10.0.1.110 inside
hostname(config)# dhcpd dns 198.162.1.2 198.162.1.3
hostname(config)# dhcpd wins 198.162.1.4
hostname(config)# dhcpd lease 3000
hostname(config)# dhcpd ping_timeout 1000
hostname(config)# dhcpd domain example.com
hostname(config)# dhcpd enable inside
Related Commands
Command
|
Description
|
clear configure dhcpd
|
Removes all DHCP server settings.
|
show running-config dhcpd
|
Displays the current DHCP server configuration.
|
dhcpd update dns
To enable a DHCP server to perform DDNS updates, use the dhcpd update dns command in global configuration mode. To disable DDNS by a DHCP server, use the no form of this command.
dhcpd update dns [both] [override] [interface srv_ifc_name]
no dhcpd update dns [both] [override] [interface srv_ifc_name]
Syntax Description
both
|
Specifies that the DHCP server updates both A and PTR DNS RRs.
|
interface
|
Specifies the ASA interface to which the DDNS updates apply.
|
override
|
Specifies that the DHCP server overrides DHCP client requests.
|
srv_ifc_name
|
Specifies an interface to apply this option to.
|
Defaults
By default, the DHCP server performs PTR RR updates only.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Global configuration
|
•
|
—
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
7.2(1)
|
This command was introduced.
|
Usage Guidelines
DDNS updates the name-to-address and address-to-name mapping maintained by DNS. Updates are performed in conjunction with a DHCP server. The dhcpd update dns command enables updates by the server.
Name and address mapping is contained in two types of RRs:
•
The A resource record contains domain name-to IP-address mapping.
•
The PTR resource record contains IP addres- to-domain name mapping.
DDNS updates can be used to maintain consistent information between the A and PTR RR types.
Using the dhcpd update dns command, the DHCP server can be configured to perform both A and PRT RR updates or PTR RR updates only. It can also be configured to override update requests from the DHCP client.
Examples
The following example configures the DDNS server to perform both A and PTR updates and override requests from the DHCP client:
hostname(config)# dhcpd update dns both override
Related Commands
Command
|
Description
|
ddns
|
Specifies a DDNS update method type for a created DDNS method.
|
ddns update
|
Associates a DDNS update method with an ASA interface or a DDNS update hostname.
|
ddns update method
|
Creates a method for dynamically updating DNS resource records.
|
dhcp-client update dns
|
Configures the update parameters that the DHCP client passes to the DHCP server.
|
interval maximum
|
Configures the maximum interval between update attempts by a DDNS update method.
|
dhcpd wins
To define the WINS server IP addresses for DHCP clients, use the dhcpd wins command in global configuration mode. To remove the WINS server IP addresses from the configuration, use the no form of this command.
dhcpd wins server1 [server2] [interface if_name]
no dhcpd wins [server1 [server2]] [interface if_name]
Syntax Description
interface if_name
|
Specifies the interface to which values entered to the server apply. If no interface is specified, values are applied to all servers.
|
server1
|
Specifies the IP address of the primary Microsoft NetBIOS name server (WINS server).
|
server2
|
(Optional) Specifies the IP address of the alternate Microsoft NetBIOS name server (WINS server).
|
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Global configuration
|
•
|
•
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
The dhcpd wins command lets you specify the addresses of the WINS servers for the DHCP client. The no dhcpd wins command removes the WINS server IP addresses from the configuration.
Examples
The following example shows how to specify WINS server information that is sent to DHCP clients:
hostname(config)# dhcpd address 10.0.1.101-10.0.1.110 inside
hostname(config)# dhcpd dns 198.162.1.2 198.162.1.3
hostname(config)# dhcpd wins 198.162.1.4
hostname(config)# dhcpd lease 3000
hostname(config)# dhcpd ping_timeout 1000
hostname(config)# dhcpd domain example.com
hostname(config)# dhcpd enable inside
Related Commands
Command
|
Description
|
clear configure dhcpd
|
Removes all DHCP server settings.
|
dhcpd address
|
Specifies the address pool used by the DHCP server on the specified interface.
|
dhcpd dns
|
Defines the DNS servers for DHCP clients.
|
show dhcpd
|
Displays DHCP binding, statistical, or state information.
|
show running-config dhcpd
|
Displays the current DHCP server configuration.
|
dhcprelay enable
To enable the DHCP relay agent, use the dhcprelay enable command in global configuration mode. To disable the DHCP relay agent, use the no form of this command.
dhcprelay enable interface_name
no dhcprelay enable interface_name
Syntax Description
interface_name
|
Name of the interface on which the DHCP relay agent accepts client requests.
|
Defaults
The DHCP relay agent is disabled.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Global configuration
|
•
|
—
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
The DHCP relay agent allows DHCP requests to be forwarded from a specified ASA interface to a specified DHCP server.
For the ASA to start the DHCP relay agent with the dhcprelay enable interface_name command, you must have a dhcprelay server command already in the configuration. Otherwise, the ASA displays an error message similar to the following:
DHCPRA: Warning - There are no DHCP servers configured!
No relaying can be done without a server!
Use the 'dhcprelay server <server_ip> <server_interface>' command
You cannot enable DHCP relay under the following conditions:
•
You cannot enable DHCP relay and the DHCP relay server on the same interface.
•
You cannot enable DCHP relay and a DHCP server (dhcpd enable) on the same interface.
•
The DHCP relay agent cannot be enabled if the DHCP server is also enabled.
•
For multiple context mode, you cannot enable DHCP relay on an interface that is used by more than one context (a shared VLAN).
The no dhcprelay enable interface_name command removes the DHCP relay agent configuration for the interface that is specified by the interface_name argument only.
Examples
The following example shows how to configure the DHCP relay agent for a DHCP server with an IP address of 10.1.1.1 on the outside interface of the ASA, client requests on the inside interface of the ASA, and a timeout value up to 90 seconds:
hostname(config)# dhcprelay server 10.1.1.1 outside
hostname(config)# dhcprelay timeout 90
hostname(config)# dhcprelay enable inside
hostname(config)# show running-config dhcprelay
dhcprelay server 10.1.1.1 outside
The following example shows how to disable the DHCP relay agent:
hostname(config)# no dhcprelay enable inside
hostname(config)# show running-config dhcprelay
dhcprelay server 10.1.1.1 outside
Related Commands
Command
|
Description
|
clear configure dhcprelay
|
Removes all DHCP relay agent settings.
|
debug dhcp relay
|
Displays debugging information for the DHCP relay agent.
|
dhcprelay server
|
Specifies the DHCP server to which the DHCP relay agent forwards DHCP requests.
|
dhcprelay setroute
|
Defines IP address that the DHCP relay agent uses as the default router address in DHCP replies.
|
show running-config dhcprelay
|
Displays the current DHCP relay agent configuration.
|
dhcprelay information trust-all
To configure a specified interface as trusted, use the dhcprelay information trust-all command in global configuration mode.
dhcprelay information trust-all
Syntax Description
This command has no arguments or keywords.
Defaults
No default behaviors or values.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Global configuration
|
•
|
—
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
9.1(2)
|
This command was introduced.
|
Usage Guidelines
This command configures a given interface as trusted. To view the interface-specific trusted configuration, use the show running-config dhcprelay interface command in interface configuration mode. To configure a given interface as trusted in interface configuration mode, use the dhcprelay information trusted command. To view a given interface as trusted in global configuration mode, use the show running-config dhcprelay command.
Examples
The following example shows how to configure a specified interface as trusted in global configuration mode:
hostname(config-if)# interface vlan501
hostname(config-if)# nameif inside
hostname(config)# dhcprelay information trust-all
hostname(config)# show running-config dhcprelay
dhcprelay information trust-all
Related Commands
Command
|
Description
|
clear configure dhcprelay
|
Removes all DHCP relay agent settings.
|
dhcprelay enable
|
Enables the DHCP relay agent on the specified interface.
|
dhcprelay setroute
|
Defines IP address that the DHCP relay agent uses as the default router address in DHCP replies.
|
dhcprelay timeout
|
Specifies the timeout value for the DHCP relay agent.
|
show running-config dhcprelay
|
Displays the current DHCP relay agent configuration.
|
dhcprelay information trusted
To configure a specified interface as trusted, use the dhcprelay information trusted command in interface configuration mode.
dhcprelay information trusted
Syntax Description
This command has no arguments or keywords.
Defaults
No default behaviors or values.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Interface configuration
|
•
|
—
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
9.1(2)
|
This command was introduced.
|
Usage Guidelines
This command configures a given interface as trusted. To view the interface-specific trusted configuration, use the show running-config dhcprelay interface command in interface configuration mode. To configure a given interface as trusted in global configuration mode, use the dhcprelay information trust-all command. To view a given interface as trusted in global configuration mode, use the show running-config dhcprelay command.
Examples
The following example shows how to configure a specified interface as trusted:
hostname(config-if)# interface gigabitEthernet 0/0
hostname(config-if)# nameif inside
hostname(config-if)# dhcprelay information trusted
hostname(config)# show running-config dhcprelay
interface gigabitEthernet 0/0
dhcprelay information trusted
Related Commands
Command
|
Description
|
clear configure dhcprelay
|
Removes all DHCP relay agent settings.
|
dhcprelay enable
|
Enables the DHCP relay agent on the specified interface.
|
dhcprelay setroute
|
Defines IP address that the DHCP relay agent uses as the default router address in DHCP replies.
|
dhcprelay timeout
|
Specifies the timeout value for the DHCP relay agent.
|
show running-config dhcprelay
|
Displays the current DHCP relay agent configuration.
|
dhcprelay server (global)
To specify the DHCP server to which DHCP requests are forwarded, use the dhcpreplay server command in global configuration mode. To remove the DHCP server from the DHCP relay configuration, use the no form of this command.
dhcprelay server [interface_name]
no dhcprelay server [interface_name]
Syntax Description
interface_name
|
Specifies the name of the ASA interface on which the DHCP server resides.
|
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Global configuration
|
•
|
—
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
The DHCP relay agent allows DHCP requests to be forwarded from a specified ASA interface to a specified DHCP server. You can add up to ten DHCP relay servers per interface. You must add at least one dhcprelay server command to the ASA configuration before you can enter the dhcprelay enable command. You cannot configure a DHCP client on an interface that has a DHCP relay server configured.
The dhcprelay server command opens UDP port 67 on the specified interface and starts the DHCP relay task as soon as the dhcprelay enable command is added to the configuration.
Examples
The following example shows how to configure the DHCP relay agent for a DHCP server with an IP address of 10.1.1.1 on the outside interface of the ASA, client requests on the inside interface of the ASA, and a timeout value of up to 90 seconds:
hostname(config)# dhcprelay server 10.1.1.1 outside
hostname(config)# dhcprelay timeout 90
hostname(config)# dhcprelay enable inside
hostname(config)# show running-config dhcprelay
dhcprelay server 10.1.1.1 outside
Related Commands
Command
|
Description
|
clear configure dhcprelay
|
Removes all DHCP relay agent settings.
|
dhcprelay enable
|
Enables the DHCP relay agent on the specified interface.
|
dhcprelay setroute
|
Defines IP address that the DHCP relay agent uses as the default router address in DHCP replies.
|
dhcprelay timeout
|
Specifies the timeout value for the DHCP relay agent.
|
show running-config dhcprelay
|
Displays the current DHCP relay agent configuration.
|
dhcprelay server (interface) (9.1(2) and later)
To specify the DHCP relay interface server to which DHCP requests are forwarded, use the dhcpreplay server command in interface configuration mode. To remove the DHCP relay interface server from the DHCP relay configuration, use the no form of this command.
dhcprelay server ip_address
no dhcprelay server ip_address
Syntax Description
ip_address
|
Specifies the IP address of the DHCP relay interface server to which the DHCP relay agent forwards client DHCP requests.
|
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Interface configuration
|
•
|
—
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
9.1(2)
|
This command was introduced.
|
Usage Guidelines
The DHCP relay agent allows DHCP requests to be forwarded from a specified ASA interface to a specified DHCP server. You can add up to four DHCP relay servers per interface. You must add at least one dhcprelay server command to the ASA configuration before you can enter the dhcprelay enable command. You cannot configure a DHCP client on an interface that has a DHCP relay server configured.
The dhcprelay server command opens UDP port 67 on the specified interface and starts the DHCP relay task as soon as the dhcprelay enable command is added to the configuration.
In the interface configuration mode, you can use the dhcprelay server ip_address command to configure a DHCP relay server (called a helper) address on a per-interface basis. This means that when a DHCP request is received on an interface and it has helper addresses configured, then the request is forwarded to only those servers.
When you use the no dhcprelay server ip_address command, the interface stops forwarding DHCP packets to that server and removes the DHCP relay agent configuration for the DHCP server that is specified by the ip_address argument only.
This command takes precedence over a DHCP relay server that has been configured in global configuration mode. This means that the DHCP relay agent forwards the client discovery message first to the DHCP relay interface server, then to the DHCP global relay server.
Examples
The following example shows how to configure the DHCP relay agent for a DHCP relay interface server with an IP address of 10.1.1.1 on the outside interface of the ASA, client requests on the inside interface of the ASA, and a timeout value of up to 90 seconds:
hostname(config)# interface vlan 10
hostname(config-if)# nameif inside
hostname(config-if)# dhcprelay server 10.1.1.1
hostname(config-if)# exit
hostname(config)# dhcprelay timeout 90
hostname(config)# dhcprelay enable inside
hostname(config)# show running-config dhcprelay
dhcprelay server 10.1.1.1
Related Commands
Command
|
Description
|
clear configure dhcprelay
|
Removes all DHCP relay agent settings.
|
dhcprelay enable
|
Enables the DHCP relay agent on the specified interface.
|
dhcprelay setroute
|
Defines IP address that the DHCP relay agent uses as the default router address in DHCP replies.
|
dhcprelay timeout
|
Specifies the timeout value for the DHCP relay agent.
|
show running-config dhcprelay
|
Displays the current DHCP relay agent configuration.
|
dhcprelay setroute
To set the default gateway address in the DHCP reply, use the dhcprelay setroute command in global configuration mode. To remove the default router, use the no form of this command.
dhcprelay setroute interface
no dhcprelay setroute interface
Syntax Description
interface
|
Configures the DHCP relay agent to change the first default IP address (in the packet sent from the DHCP server) to the address of interface.
|
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Global configuration
|
•
|
—
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
This command causes the default IP address of the DHCP reply to be substituted with the address of the specified ASA interface. The dhcprelay setroute interface command lets you enable the DHCP relay agent to change the first default router address (in the packet sent from the DHCP server) to the address of interface.
If there is no default router option in the packet, the ASA adds one containing the address of interface. This action allows the client to set its default route to point to the ASA.
When you do not configure the dhcprelay setroute interface command (and there is a default router option in the packet), it passes through the ASA with the router address unaltered.
Examples
The following example shows how to set the default gateway in the DHCP reply from the external DHCP server to the inside interface of the ASA:
hostname(config)# dhcprelay server 10.1.1.1 outside
hostname(config)# dhcprelay timeout 90
hostname(config)# dhcprelay setroute inside
hostname(config)# dhcprelay enable inside
Related Commands
Command
|
Description
|
clear configure dhcprelay
|
Removes all DHCP relay agent settings.
|
dhcprelay enable
|
Enables the DHCP relay agent on the specified interface.
|
dhcprelay server
|
Specifies the DHCP server that the DHCP relay agent forwards DHCP requests to.
|
dhcprelay timeout
|
Specifies the timeout value for the DHCP relay agent.
|
show running-config dhcprelay
|
Displays the current DHCP relay agent configuration.
|
dhcprelay timeout
To set the DHCP relay agent timeout value, use the dhcprelay timeout command in global configuration mode. To restore the timeout value to its default value, use the no form of this command.
dhcprelay timeout seconds
no dhcprelay timeout
Syntax Description
seconds
|
Specifies the number of seconds that are allowed for DHCP relay address negotiation.
|
Defaults
The default value for the DHCP relay timeout is 60 seconds.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Global configuration
|
•
|
—
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
The dhcprelay timeout command lets you set the amount of time, in seconds, allowed for responses from the DHCP server to pass to the DHCP client through the relay binding structure.
Examples
The following example shows how to configure the DHCP relay agent for a DHCP server with an IP address of 10.1.1.1 on the outside interface of the ASA, client requests on the inside interface of the ASA, and a timeout value up to 90 seconds:
hostname(config)# dhcprelay server 10.1.1.1 outside
hostname(config)# dhcprelay timeout 90
hostname(config)# dhcprelay enable inside
hostname(config)# show running-config dhcprelay
dhcprelay server 10.1.1.1 outside
Related Commands
Command
|
Description
|
clear configure dhcprelay
|
Removes all DHCP relay agent settings.
|
dhcprelay enable
|
Enables the DHCP relay agent on the specified interface.
|
dhcprelay server
|
Specifies the DHCP server to which the DHCP relay agent forwards DHCP requests.
|
dhcprelay setroute
|
Defines IP address that the DHCP relay agent uses as the default router address in DHCP replies.
|
show running-config dhcprelay
|
Displays the current DHCP relay agent configuration.
|
dialog
To customize dialog box messages displayed to WebVPN users, use the dialog command in webvpn customization configuration mode. To remove the command from the configuration and cause the value to be inherited, use the no form of this command.
dialog {title | message | border} style value
no dialog {title | message | border} style value
Syntax Description
border
|
Specifies a change to the border.
|
message
|
Specifies a change to the message.
|
style
|
Specifies a change to the style.
|
title
|
Specifies a change to the title.
|
value
|
The actual text or or CSS parameters to display (the maximum is 256 characters).
|
Defaults
The default title style is background-color:#669999;color:white.
The default message style is background-color:#99CCCC;color:black.
The default border style is border:1px solid black;border-collapse:collapse.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Webvpn customization configuration
|
•
|
—
|
•
|
—
|
—
|
Command History
Release
|
Modification
|
7.1(1)
|
This command was introduced.
|
Usage Guidelines
The style option is expressed as any valid CSS parameters. Describing these parameters is beyond the scope of this document. For more information about CSS parameters, consult CSS specifications at the World Wide Web Consortium website at www.w3.org. Appendix F of the CSS 2.1 Specification contains a convenient list of CSS parameters, and is available at www.w3.org/TR/CSS21/propidx.html.
Here are some tips for making the most common changes to the WebVPN pages—the page colors:
•
You can use a comma-separated RGB value, an HTML color value, or the name of the color if recognized in HTML.
•
The RGB format is 0,0,0, a range of decimal numbers from 0 to 255 for each color (red, green, blue); the comma-separated entry indicates the level of intensity of each color to combine with the others.
•
The HTML format is #000000, six digits in hexadecimal format; the first and second represent red, the third and fourth green, and the fifth and sixth represent blue.
Note
To easily customize the WebVPN pages, we recommend that you use ASDM, which has convenient features for configuring style elements, including color swatches and preview capabilities.
Examples
The following example customizes the dialog box message, changing the foreground color to blue:
hostname(config-webvpn)# customization cisco
hostname(config-webvpn-custom)# dialog message style color:blue
Related Commands
Command
|
Description
|
application-access
|
Customizes the Application Access box of the WebVPN Home page.
|
browse-networks
|
Customizes the Browse Networks box of the WebVPN Home page.
|
web-bookmarks
|
Customizes the Web Bookmarks title or links on the WebVPN Home page.
|
file-bookmarks
|
Customizes the File Bookmarks title or links on the WebVPN Home page.
|
dir
To display the directory contents, use the dir command in privileged EXEC mode.
dir [/all] [all-filesystems] [/recursive] [ disk0: | disk1: | flash: | system:] [path]
Syntax Description
/all
|
(Optional) Displays all files.
|
/recursive
|
(Optional) Displays the directory contents recursively.
|
all-filesystems
|
(Optional) Displays the files of all filesystems.
|
disk0:
|
(Optional) Specifies the internal flash memory, followed by a colon.
|
disk1:
|
(Optional) Specifies the external flash memory card, followed by a colon.
|
flash:
|
(Optional) Displays the directory contents of the default flash partition.
|
path
|
(Optional) Specifies a specific path.
|
system:
|
(Optional) Displays the directory contents of the file system.
|
Defaults
If you do not specify a directory, the directory is the current working directory by default.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Privileged EXEC
|
•
|
•
|
•
|
—
|
•
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
The dir command without keywords or arguments displays the directory contents of the current directory.
Examples
The following example shows how to display the directory contents:
1 -rw- 1519 10:03:50 Jul 14 2003 my_context.cfg
2 -rw- 1516 10:04:02 Jul 14 2003 my_context.cfg
3 -rw- 1516 10:01:34 Jul 14 2003 admin.cfg
60985344 bytes total (60973056 bytes free)
The following example shows how to display recursively the contents of the entire file system:
hostname# dir /recursive disk0:
1 -rw- 1519 10:03:50 Jul 14 2003 my_context.cfg
2 -rw- 1516 10:04:02 Jul 14 2003 my_context.cfg
3 -rw- 1516 10:01:34 Jul 14 2003 admin.cfg
60985344 bytes total (60973056 bytes free)
The following example shows how to display the contents of the flash partition:
1 -rw- 1519 10:03:50 Jul 14 2003 my_context.cfg
2 -rw- 1516 10:04:02 Jul 14 2003 my_context.cfg
3 -rw- 1516 10:01:34 Jul 14 2003 admin.cfg
60985344 bytes total (60973056 bytes free)
Related Commands
Command
|
Description
|
cd
|
Changes the current working directory to the one specified.
|
pwd
|
Displays the current working directory.
|
mkdir
|
Creates a directory.
|
rmdir
|
Removes a directory.
|
disable
To exit privileged EXEC mode and return to unprivileged EXEC mode, use the disable command in privileged EXEC mode.
disable
Syntax Description
This command has no arguments or keywords.
Defaults
No default behaviors or values.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Privileged EXEC
|
•
|
•
|
•
|
•
|
•
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
Use the enable command to enter privileged mode. The disable command allows you to exit privileged mode and returns you to an unprivileged mode.
Examples
The following example shows how to enter privileged mode:
The following example shows how to exit privileged mode:
Related Commands
Command
|
Description
|
enable
|
Enables privileged EXEC mode.
|
disable (cache)
To disable caching for WebVPN, use the disable command in cache configuration mode. To reenable caching, use the no version of this command.
disable
no disable
Defaults
Caching is enabled with default settings for each cache attribute.
Command Modes
The following table shows the modes in which you enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Cache configuration
|
•
|
—
|
•
|
—
|
—
|
Command History
Release
|
Modification
|
7.1(1)
|
This command was introduced.
|
Usage Guidelines
Caching stores frequently reused objects in the system cache, which reduces the need to perform repeated rewriting and compressing of content. It reduces traffic between WebVPN and both the remote servers and end-user browsers, with the result that many applications run much more efficiently.
Examples
The following example shows how to disable caching, and then how to reenable it.
hostname(config-webvpn)#
cache
hostname(config-webvpn-cache)# disable
hostname(config-webvpn-cache)# no disable
hostname(config-webvpn-cache)#
Related Commands
Command
|
Description
|
cache
|
Enters webvpn cache configuration mode.
|
cache-compressed
|
Configures WebVPN cache compression.
|
expiry-time
|
Configures the expiration time for caching objects without revalidating them.
|
lmfactor
|
Sets a revalidation policy for caching objects that have only the last-modified timestamp.
|
max-object-size
|
Defines the maximum size of an object to cache.
|
min-object-size
|
Defines the minimum sizze of an object to cache.
|
disable service-settings
To disable the service settings on IP phones when using the Phone Proxy feature, use the disable service-settings command in phone-proxy configuration mode. To preserve the settings on the IP phones, use the no form of this command.
disable service-settings
no disable service-settings
Syntax Description
There are no arguments or keywords for this command.
Defaults
The service settings are disabled by default.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Phone-proxy configuration
|
•
|
—
|
•
|
—
|
—
|
Command History
Release
|
Modification
|
8.0(4)
|
This command was introduced.
|
Usage Guidelines
By default, the following settings are disabled on the IP phones:
•
PC Port
•
Gratuitous ARP
•
Voice VLAN access
•
Web Access
•
Span to PC Port
To preserve the settings configured on the CUCM for each IP phone configured, configure the no disable service-settings command.
Examples
The following example shows how to preserve the settings of the IP phones that use the Phone Proxy feature on the ASA:
hostname(config-phone-proxy)#
no disable service-settings
Related Commands
Command
|
Description
|
phone-proxy
|
Configures the Phone Proxy instance.
|
show phone-proxy
|
Displays Phone Proxy specific information.
|
display
To display attribute value pairs that the ASA writes to the DAP attribute database, enter the display command in dap test attributes mode.
display
Command Default
No default value or behaviors.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Dap test attributes
|
•
|
•
|
•
|
—
|
—
|
Command History
Release
|
Modification
|
8.0(2)
|
This command was introduced.
|
Usage Guidelines
Normally the ASA retrieves user authorization attributes from the AAA server and retrieves endpoint attributes from Cisco Secure Desktop, Host Scan, CNA or NAC. For the test command, you specify the user authorization and endpoint attributes in this attributes mode. The ASA writes them to an attribute database that the DAP subsystem references when evaluating the AAA selection attributes and endpoint select attributes for a DAP record. The display command lets you display these attributes to the console.
Related Commands
Command
|
Description
|
attributes
|
Enters attributes configuration mode, in which you can set attribute value pairs.
|
dynamic-access-policy-record
|
Creates a DAP record.
|
test dynamic-access-policy attributes
|
Enters attributes submode.
|
test dynamic-access-policy execute
|
Executes the logic that generates DAP and displays the resulting access policies to the console.
|
l
distance eigrp
To configure the administrative distances of internal and external EIGRP routes, use the distance eigrp command in router configuration mode. To restore the default values, use the no form of this command.
distance eigrp internal-distance external-distance
no distance eigrp
Syntax Description
external-distance
|
Administrative distance for EIGRP external routes. External routes are those for which the best path is learned from a neighbor external to the autonomous system. Valid values are from 1 to 255.
|
internal-distance
|
Administrative distance for EIGRP internal routes. Internal routes are those that are learned from another entity within the same autonomous system. Valid values are from 1 to 255.
|
Defaults
The default values are as follows:
•
external-distance is 170
•
internal-distance is 90
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Router configuration
|
•
|
—
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
8.0(2)
|
This command was introduced.
|
9.0(1)
|
Multiple context mode is supported.
|
Usage Guidelines
Because every routing protocol has metrics based on algorithms that are different from the other routing protocols, it is not always possible to determine the "best path" for two routes to the same destination that were generated by different routing protocols. Administrative distance is a route parameter that the ASA uses to select the best path when there are two or more different routes to the same destination from two different routing protocols.
If you have more than one routing protocol running on the ASA, you can use the distance eigrp command to adjust the default administrative distances of routes discovered by the EIGRP routing protocol in relation to the other routing protocols. Table 18-1 lists the default administrative distances for the routing protocols supported by the ASA.
Table 18-1 Default Administrative Distances
Route Source
|
Default Administrative Distance
|
Connected interface
|
0
|
Static route
|
1
|
EIGRP summary route
|
5
|
Internal EIGRP
|
90
|
OSPF
|
110
|
RIP
|
120
|
EIGRP external route
|
170
|
Unknown
|
255
|
The no form of the command does not take any keywords or arguments. Using the no form of the command restores the default administrative distance for both internal and external EIGRP routes.
Examples
The following example uses the distance eigrp command to set the administrative distance of all EIGRP internal routes to 80 and all EIGRP external routes to 115. Setting the EIGRP external route administrative distance to 115 would give routes discovered by EIGRP to a specific destination preference over the same routes discovered by RIP but not by OSPF.
hostname(config)# router eigrp 100
hostname(config-router)# network 192.168.7.0
hostname(config-router)# network 172.16.0.0
hostname(config-router)# distance eigrp 90 115
Related Commands
Command
|
Description
|
router eigrp
|
Creates an EIGRP routing process and enters configuration mode for that process.
|
distance (OSPFv3)
To define OSPFv3 route administrative distances based on route type, use the distance command in IPv6 router configuration mode. To restore the default values, use the no form of this command.
distance [ospf {external | intra-area | inter-area}] distance
no distance [ospf {external | intra-area | inter-area}] distance
Syntax Description
distance
|
Specifies the administrative distance. Valid values range from 10 to 254.
|
external
|
(Optional) Specifies external type 5 and type 7 routes for OSPFv3 routes.
|
inter-area
|
(Optional) Specifies the inter-area routes for OSPFv3 routes.
|
intra-area
|
(Optional) Specifies the intra-area routes for OSPFv3 routes.
|
ospf
|
(Optional) Specifies the administrative distance for OSPFv3 routes.
|
Defaults
No default behavior or values.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
IPv6 router configuration
|
•
|
—
|
•
|
—
|
—
|
Command History
Release
|
Modification
|
9.0(1)
|
This command was introduced.
|
Usage Guidelines
Use this command to set the administrative distance for OSPFv3 routes.
Examples
The following example sets the administrative distance for external type 5 and type 7 routes for OSPFv3 to 200:
hostname(config-if)# ipv6 router ospf
hostname(config-router)# distance ospf external 200
Related Commands
Command
|
Description
|
default-information originate
|
Generates a default external route into an OSPFv3 routing domain.
|
redistribute
|
Redistributes IPv6 routes from one routing domain into another routing domain.
|
distance ospf (OSPFv2)
To define OSPFv2 route administrative distances based on route type, use the distance ospf command in router configuration mode. To restore the default values, use the no form of this command.
distance ospf [intra-area d1] [inter-area d2] [external d3]
no distance ospf
Syntax Description
d1, d2, and d3
|
Specifies the distance for each route type. Valid values range from 1 to 255.
|
external
|
(Optional) Sets the distance for routes from other routing domains that are learned by redistribution.
|
inter-area
|
(Optional) Sets the distance for all routes from one area to another area.
|
intra-area
|
(Optional) Sets the distance for all routes within an area.
|
Defaults
The default values for d1, d2, and d3 are 110.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Router configuration
|
•
|
—
|
•
|
—
|
—
|
Command History
Release
|
Modification
|
7.0(1)
|
This command was introduced.
|
Usage Guidelines
You must specify at least one keyword and argument. You can enter the commands for each type of administrative distance separately, however they appear as a single command in the configuration. If you reenter an administrative distance, the administrative distance for only that route type changes; the administrative distances for any other route types remain unaffected.
The no form of the command does not take any keywords or arguments. Using the no form of the command restores the default administrative distance for all of the route types. If you want to restore the default administrative distance for a single route type when you have multiple route types configured, you can do one of the following:
•
Manually set that route type to the default value.
•
Use the no form of the command to remove the entire configuration and then reenter the configurations for the route types that you want to keep.
Examples
The following example sets the administrative distance of external routes to 150:
hostname(config-router)# distance ospf external 105
The following example shows how entering separate commands for each route type appears as a single command in the router configuration:
hostname(config-rtr)# distance ospf intra-area 105 inter-area 105
hostname(config-rtr)# distance ospf intra-area 105
hostname(config-rtr)# distance ospf external 105
hostname(config-rtr)# exit
hostname(config)# show running-config router ospf 1
distance ospf intra-area 105 inter-area 105 external 105
The following example shows how to set each administrative distance to 105, and then change only the external administrative distance to 150. The show running-config router ospf command shows how only the external route type value changed, while the other route types retained the value previously set.
hostname(config-rtr)# distance ospf external 105 intra-area 105 inter-area 105
hostname(config-rtr)# distance ospf external 150
hostname(config-rtr)# exit
hostname(config)# show running-config router ospf 1
distance ospf intra-area 105 inter-area 105 external 150
Related Commands
Command
|
Description
|
router ospf
|
Enters router configuration mode for OSPFv2.
|
show running-config router
|
Displays the OSPFv2 commands in the global router configuration.
|
distribute-list in
To filter incoming routing updates, use the distribute-list in command in router configuration mode. To remove the filtering, use the no form of this command.
distribute-list acl in [interface if_name]
no distribute-list acl in [interface if_name]
Syntax Description
acl
|
Name of a standard access list.
|
interface if_name
|
(Optional) The interface on which to apply the incoming routing updates. Specifying an interface causes the access list to be applied only to routing updates received on that interface.
|
Defaults
Networks are not filtered in incoming updates.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Router configuration
|
•
|
—
|
•
|
•
|
—
|
Command History
Release
|
Modification
|
7.2(1)
|
This command was introduced.
|
9.0(1)
|
Multiple context mode is supported.
|
Usage Guidelines
If no interface is specified, the access list will be applied to all incoming updates.
Examples
The following example filters RIP routing updates received on the outside interface. It accepts routes in the 10.0.0.0 network and discards all others.
hostname(config)# access-list ripfilter permit 10.0.0.0
hostname(config)# access-list ripfilter deny any
hostname(config)# router rip
hostname(config-router)# network 10.0.0.0
hostname(config-router)# distribute-list ripfilter in interface outside
The following example filters EIGRP routing updates received on the outside interface. It accepts routes in the 10.0.0.0 network and discards all others.
hostname(config)# access-list eigrp_filter permit 10.0.0.0
hostname(config)# access-list eigrp_filter deny any
hostname(config)# router eigrp 100
hostname(config-router)# network 10.0.0.0
hostname(config-router)# distribute-list eigrp_filter in interface outside
Related Commands
Command
|
Description
|
distribute-list out
|
Filters outgoing routing updates.
|
router eigrp
|
Enters router configuration mode for the EIGRP routing process.
|
router rip
|
Enters router configuration mode for the RIP routing process.
|
show running-config router
|
Displays the commands in the global router configuration.
|
distribute-list out
To filter outgoing routing updates, use the distribute-list out command in router configuration mode. To remove the filtering, use the no form of this command.
distribute-list acl out [interface if_name] [eigrp as_number | rip | ospf pid | static | connected]
no distribute-list acl out [interface if_name] [eigrp as_number | rip | ospf pid | static | connected]
Syntax Description
acl
|
Name of a standard access list.
|
connected
|
(Optional) Filters only connected routes.
|
eigrp as_number
|
(Optional) Filters only EIGRP routes from the specified autonomous system number. The as_number argument is the autonomous system number of the EIGRP routing process on the ASA.
|
interface if_name
|
(Optional) The interface on which to apply the outgoing routing updates. Specifying an interface causes the access list to be applied only to routing updates received on that interface.
|
ospf pid
|
(Optional) Filters only OSPF routes discovered by the specified OSPF process.
|
rip
|
(Optional) Filters only RIP routes.
|
static
|
(Optional) Filters only static routes.
|
Defaults
Networks are not filtered in sent updates.
Command Modes
The following table shows the modes in which you can enter the command:
Command Mode
|
Firewall Mode
|
Security Context
|
Routed
|
Transparent
|
Single
|
Multiple
|
Context
|
System
|
Router configuration
|
•
|
—
|
•
|
—
|
—
|
Command History
Release
|
Modification
|
7.2(1)
|
This command was introduced.
|
8.0(2)
|
The eigrp keyword was added.
|
Usage Guidelines
If no interface is specified, the access list will be applied to all outgoing updates.
Examples
The following example prevents the 10.0.0.0 network from being advertised in RIP updates sent out of any interface:
hostname(config)# access-list ripfilter deny 10.0.0.0
hostname(config)# access-list ripfilter permit any
hostname(config)# router rip
hostname(config-router)# network 10.0.0.0
hostname(config-router)# distribute-list ripfilter out
The following example prevents the EIGRP routing process from advertising the 10.0.0.0 network on the outside interface:
hostname(config)# access-list eigrp_filter deny 10.0.0.0
hostname(config)# access-list eigrp_filter permit any
hostname(config)# router eigrp 100
hostname(config-router)# network 10.0.0.0
hostname(config-router)# distribute-list eigrp_filter out interface outside
Related Commands
Command
|
Description
|
distribute-list in
|
Filters incoming routing updates.
|
router eigrp
|
Enters router configuration mode for the EIGRP routing process.
|
router rip
|
Enters router configuration mode for the RIP routing process.
|
show running-config router
|
Displays the commands in the global router configuration.
|