Disabling the BGP AS_PATH Check Function

A device can be configured so that the AS_PATH check function for routes learned from a specific location is disabled, and routes that contain the recipient BGP speaker's AS number are not rejected.
  1. Enter the configure terminal command to access global configuration mode. 
    device# configure terminal
  2. Enter the router bgp command to enable BGP routing. 
    device(config)# router bgp
  3. Enter the address-family ipv6 unicast command to enter IPv6 address family unicast configuration mode. 
    device(config-bgp-router)# address-family ipv6 unicast
  4. Enter the neighbor allowas-in command with an IPv6 address and specify a number to disable the BGP AS_PATH check function, and specify the number of times that the AS path of a received route may contain the recipient BGP speaker's AS number and still be accepted. 
    device(config-bgp-ipv6u)# neighbor 2001:db8:e0ff:783a::4 allowas-in 3

The following example specifies that the AS path of a received route may contain the recipient BGP speaker's AS number three times and still be accepted. 

device# configure terminal
device(config)# router bgp
device(config-bgp-router)# address-family ipv6 unicast
device(config-bgp-ipv6u)# neighbor 2001:db8:e0ff:783a::4 allowas-in 3
Parent topic: BGP4+