configure bgp peer-group allowas-in

configure bgp peer-group peer-group-name {address-family [ipv4-unicast | ipv4-multicast |ipv6-unicast | ipv6-multicast |vpnv4]} allowas-in {max-as-occurrence as-count}

Description

Configures BGP to receive and accept a looped BGP route from the neighbors of the specified peer group, provided the number of occurrences of local AS number in AS-Path is less than or equal to that specified in as-count.

Syntax Description

peer-group-name Specifies a peer group.
ipv4-unicast Specifies the IPv4 unicast address family.
ipv4-multicast Specifies an IPv4 multicast address family.
ipv6-unicast Specifies the IPv6 unicast address family.
ipv6-multicast Specifies an IPv6 multicast address family.
vpnv4 Specifies the VPNv4 address family for Layer 3 VPN support.
as-count The maximum number of occurrences of local AS number in the received route AS-Path. If the number of occurrences of local AS number in AS-Path is more than as-count, the route is not accepted. The valid range is from 1-16.

Default

This feature is disabled by default.

If no as-count is specified, the as-count defaults to 3.

If no address family is specified, IPv4 unicast is the default.

Usage Guidelines

In a hub and spoke configuration, it becomes necessary to accept an inbound BGP route even though the route's AS-Path contains the receiver's own AS-number. In such network topologies, this feature can be enabled.

This feature can also be enabled for both IBGP and EBGP neighbors, wherever necessary.

This command applies to the current VR or VRF context.

Note

Note

BGP neighbors do not inherit the allowas-in configuration from their peer group unless you explicitly specify the acquire-all option when adding a neighbor to a peer-group.

If you do not specify an address family, this command applies to the IPv4 unicast address family. To apply this command to an address family other than the IPv4 unicast address family, you must specify the address family.

Note

Note

If the specified peer group contains IPv6 peers, it is an IPv6 peer group and you must specify an IPv6 address-family. When the specified peer group is an IPv6 peer group, this command fails if no address family is specified or if an IPv4 address-family is specified. This command also fails if an IPv6 address family is specified for an IPv4 peer-group.

To configure this feature on Layer 3 VPNs, you must configure this feature in the context of the MPLS-enabled VR; this feature is not supported for BGP neighbors on the CE (VRF) side of the PE router.

Example

The following example enables BGP to accept looped BGP routes that contains a maximum of 8 occurrences of receiver's AS-number in AS-Path attribute:

configure bgp peer-group internal allowas-in max-as-occurrence 8

History

This command was first available in ExtremeXOS 12.1.

Support for IPv6 was added in ExtremeXOS 12.6 BGP.

Support for Layer 3 VPNs was added in ExtremeXOS 15.3.

Platform Availability

This command is available on platforms that support the appropriate license. For complete information about software licensing, including how to obtain and upgrade your license and which licenses support the BGP feature, see the Feature License Requirements document.