EXEC Commands

Pushing Out A Prefix List and Receiving a Route Refresh from a Neighbor

The command syntax to push out a prefix list and receive route refresh from a neighbor is as follows (note that any address family can be specified):

clear ip bgp x.x.x.x in prefix-filter
clear ip bgp x.x.x.x vrf foo in prefix-filter
clear ip bgp x.x.x.x ipv4 multicast in prefix-filter

When the inbound prefix list changes (or is removed), this command can be used to push out the new prefix list, and consequently receive route refresh from the neighbor based on the new prefix list.

The keyword prefix-filter will be ignored if the BGP ORF capability has not been received from the neighbor, or if the local speaker has not enabled send-orf for the neighbor.

Without the keyword prefix-filter, the command clear ip bgp x.x.x.x in would simply perform the normal route refresh from the neighbor. It does not push out the current inbound prefix list filter to the neighbor. The command is useful when using inbound routing policies other than the prefix list filter such as a route map change.

Displaying the Prefix List Received from a Neighbor

The command syntax to display the prefix list received from a neighbor is as follows:

show ip bgp neighbor x.x.x.x received prefix-filter
show ip bgp vpnv4 vrf foo neighbor x.x.x.x received prefix-filter
show ip bgp ipv4 multicast neighbor x.x.x.x received prefix-filter

Displaying Changes to the Neighbor BGP Table

Changes to the output of show ip bgp neighbor x.x.x.x reveal the following information:

AF-dependant capabilities:
      Outbound Route Filter (ORF) type (128) Prefix-list:
        Send-mode: advertised, received
    Receive-mode: advertised, received

Outbound Route Filter (ORF): sent, received (2 entries)
First update is deferred until ORF or ROUTE-REFRESH is received
Scheduled to send the Prefix-list filter test