Purpose
Command or Action
Specifies the autonomous system number and enters the
BGP configuration mode, allowing you to configure the
BGP routing process.
router bgp as-number
Example:
RP/0/RP0/CPU0:router(config)# router bgp 120
Step 2
Specifies either an IPv4 or IPv6 address family unicast and
enters address family configuration submode.
address-family
{
ipv4
|
ipv6
}
unicast
Example:
Step 3
To see a list of all the possible keywords and arguments for
this command, use the CLI help (?).
RP/0/RP0/CPU0:router(config-bgp)# address-family
ipv4 unicast
Sets the external, internal, and local administrative distances
to prefer one class of routes over another. The higher the
value, the lower the trust rating.
distance bgp
external-distance internal-distance
local-distance
Example:
Step 4
RP/0/RP0/CPU0:router(config-bgp-af)# distance bgp
20 20 200
commit
Step 5
Configuring a BGP Neighbor Group and Neighbors
Perform this task to configure BGP neighbor groups and apply the neighbor group configuration to a neighbor.
A neighbor group is a template that holds address family-independent and address family-dependent
configurations associated with the neighbor.
After a neighbor group is configured, each neighbor can inherit the configuration through the
use
command.
If a neighbor is configured to use a neighbor group, the neighbor (by default) inherits the entire configuration
of the neighbor group, which includes the address family-independent and address family-dependent
configurations. The inherited configuration can be overridden if you directly configure commands for the
neighbor or configure session groups or address family groups through the
use
command.
You can configure an address family-independent configuration under the neighbor group. An address
family-dependent configuration requires you to configure the address family under the neighbor group to
enter address family submode.
From neighbor group configuration mode, you can configure address family-independent parameters for the
neighbor group. Use the
address-family
command when in the neighbor group configuration mode.
After specifying the neighbor group name using the
neighbor group
command, you can assign options to
the neighbor group.
All commands that can be configured under a specified neighbor group can be configured under a neighbor.
Note
SUMMARY STEPS
1.
configure
2.
router bgp as-number
Routing Configuration Guide for Cisco NCS 6000 Series Routers, IOS XR Release 6.4.x
62
Implementing BGP
Configuring a BGP Neighbor Group and Neighbors