group listen (BGP view)

Function

The group listen command creates a dynamic BGP peer group.

The undo group listen command deletes a dynamic BGP peer group.

By default, no dynamic BGP peer groups are created.

Format

group group-name listen { internal | external | confederation-external }

group group-name listen

undo group group-name listen [ internal | external | confederation-external ]

Parameters

Parameter	Description	Value
group-name	Specifies the name of a dynamic BGP peer group.	The name is a string of 1 to 47 case-sensitive characters, with spaces not supported. When double quotation marks are used around the string, spaces are allowed in the string.
internal	Creates a dynamic IBGP peer group.	-
external	Creates a dynamic EBGP peer group.	-
confederation-external	Creates a dynamic confederation EBGP peer group.	-

Views

BGP view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
bgp	write

Usage Guidelines

Usage Scenario

If static BGP peers change frequently on a BGP network, you need to add or delete BGP peer configurations in response to each change, which requires a heavy maintenance workload. To address this problem, configure the dynamic BGP peer function to enable BGP to listen for BGP connection requests from a specified network segment, dynamically establish BGP peer relationships, and add these peers to the same dynamic peer group. This spares you from adding or deleting BGP peer configurations in response to each change in dynamic peers. To create a dynamic BGP peer group, run the group listen command.

After a peer is added to a dynamic peer group, the peer inherits the configurations of this peer group. If the configurations of the peer group change, the configurations of all the peers in the group change accordingly. Such implementation is the same as that of static BGP peer groups.

If a dynamic BGP peer group is created in a BGP address family, creating the same peer group in another address family does not take effect. In this case, you must run the reset bgp x.x.x.x command (x.x.x.x specifies the IP address of a dynamic BGP peer) or run the reset bgp group groupname command in the user view to allow the dynamic BGP peer group to be created in the latter address family.

Precautions

If the group listen command is run more than once, all configurations take effect.

If a dynamic BGP peer group is deleted, connections with all peers in the peer group are deleted.

Names of BGP peer groups must be unique, regardless of whether they are of dynamic or static peer groups.

If the type (IBGP or EBGP) of a dynamic BGP peer group is not specified, a dynamic IBGP peer group is created by default.

Peers in a dynamic BGP peer group share the same attribute. Peer-based attribute configuration is not allowed in a dynamic BGP peer group.

The undo group command applies to both dynamic and static BGP peer groups. If the command is run, the corresponding peer group and all its configurations are deleted. Therefore, exercise caution when running this command.

Example

# Create a dynamic IBGP peer group named in.

<HUAWEI> system-view
[~HUAWEI] bgp 100
[*HUAWEI-bgp] group in listen internal