address-family (BGP)
To enter various address family configuration modes while configuring Border Gateway Protocol (BGP), use the address-family command in an appropriate configuration mode. To disable support for an address family, use the no form of this command.
address-family {ipv4 {labeled-unicast | flowspec | unicast} | ipv6 {labeled-unicast | flowspec | unicast} | | }
no address-family
Syntax Description
ipv4 unicast |
Specifies IP Version 4 (IPv4) unicast address prefixes. |
ipv4 labeled-unicast |
Specifies IPv4 labeled-unicast address prefixes. This option is available in IPv4 neighbor configuration mode. |
ipv6 unicast |
Specifies IP Version 6 (IPv6) unicast address prefixes. |
ipv6 labeled-unicast |
Specifies IPv6 labeled-unicast address prefixes. This option is available in IPv6 neighbor configuration mode. |
Command Default
An address family must be explicitly configured in the router configuration mode for the address family to be active in BGP. Similarly, an address family must be configured under the neighbor for the BGP session to be established for that address family. An address family must be configured in router configuration mode before it can be configured under a neighbor.
Command Modes
Router configuration
Neighbor configuration
Neighbor group configuration
Flowspec configuration
Command History
Release |
Modification |
---|---|
Release 5.0.0 |
This command was introduced. |
Usage Guidelines
To use this command, you must be in a user group associated with a task group that includes appropriate task IDs. If the user group assignment is preventing you from using a command, contact your AAA administrator for assistance.
Use the address-family command to enter various address family configuration modes while configuring BGP routing sessions. When you enter the address-family command from router configuration mode, you enable the address family and enter global address family configuration mode.
The IPv4 unicast address family must be configured in router configuration mode before configuring the IPv4 labeled-unicast address family for a neighbor in neighbor configuration mode. The IPv6 unicast address family must be configured in router configuration mode before configuring the IPv6 labeled-unicast address family for a neighbor in neighbor configuration mode.
When you enter the address-family command from neighbor configuration mode, you activate the address family on the neighbor and enter neighbor address family configuration mode. IPv4 neighbor sessions support IPv4 unicast, , and labeled-unicastaddress families. IPv6 neighbor sessions support IPv6 unicast address families.
Task ID
Task ID |
Operations |
---|---|
bgp |
read, write |
Examples
The following example shows how to place the router in global address family configuration mode for the IPv4 address family:
RP/0/RP0/CPU0:router# configure
RP/0/RP0/CPU0:router(config)# router bgp 100
RP/0/RP0/CPU0:router(config-bgp)# address-family ipv4 unicast
RP/0/RP0/CPU0:router(config-bgp-af)#
RP/0/RP0/CPU0:router# configure
RP/0/RP0/CPU0:router(config)# router bgp 100
RP/0/RP0/CPU0:router(config-bgp)# address-family ipv4 flowspec
RP/0/RP0/CPU0:router(config-bgp-af)#