peer capability-advertise (BGP-VPN instance IPv4 address family view)

Function

The peer capability-advertise command enables optional BGP functions when a BGP peer advertises routes to its peer. The optional BGP functions include route-refresh, general function, 4-byte AS number, and Add-Path.

The undo peer capability-advertise command restores the default setting.

By default, the route-refresh and 4-byte AS number functions are enabled, but the general function and Add-Path are disabled.

Format

peer ipv4-address capability-advertise { conventional | route-refresh | 4-byte-as }

undo peer ipv4-address capability-advertise { conventional | route-refresh | 4-byte-as }

Parameters

Parameter	Description	Value
ipv4-address	Specifies the IPv4 address of a peer.	The value is in dotted decimal notation.
conventional	Indicates the regular function. conventional takes effect only in the BGP view or BGP-VPN instance IPv4 address family view. If conventional is specified, the device does not support all extended functions, such as route-refresh, GR, multi-address family negotiation, and Add-Path.	-
route-refresh	Indicates the route-refresh function.	-
4-byte-as	Indicates the 4-byte AS number function.	-

Views

BGP-VPN instance IPv4 address family view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
bgp	write

Usage Guidelines

Usage Scenario

There are multiple optional BGP functions when a BGP peer advertises routes to its peer. The optional BGP functions include route-refresh, general function, 4-byte AS number, and Add-Path. You can run the peer capability-advertise command to select one of the functions based on the needs on the live network.

Configuration Impact

If you enable or disable the route-refresh, general function, 4-byte AS number, or Add-Path function, the BGP peer relationship will be re-established, which can lead to a temporary network interruption. Therefore, exercise caution when running the related commands.

Example

# Configure a BGP device to advertise the route-refresh capability to its peer group.

<HUAWEI> system-view
[~HUAWEI] ip vpn-instance vpn1
[*HUAWEI-vpn-instance-vpn1] ipv4-family
[*HUAWEI-vpn-instance-vpn1-af-ipv4] route-distinguisher 100:1
[*HUAWEI-vpn-instance-vpn1-af-ipv4] quit
[*HUAWEI-vpn-instance-vpn1] quit
[*HUAWEI] bgp 100
[*HUAWEI-bgp] ipv4-family vpn-instance vpn1
[*HUAWEI-bgp-vpn1] peer 10.1.1.1 as-number 100
[*HUAWEI-bgp-vpn1] peer 10.1.1.1 enable
[*HUAWEI-bgp-vpn1] peer 10.1.1.1 capability-advertise route-refresh