6

Cisco ASR routers use IOS XE software. One can see the received IPv4 unicast prefixes from BGP neighbor before any inbound policies with sh bgp ipv4 unic neigh <neighbor-address> received routes command. Output of this command is following:

Status codes: s suppressed, d damped, h history, * valid, > best
              i - internal, r RIB-failure, S stale
Origin codes: i - IGP, e - EGP, ? - incomplete
   Network            Next Hop            Metric LocPrf Weight Path
*  10.10.10.0/24    192.168.4.9                           0 65001 65005 i

Is it possible to see communities attached to 10.10.10.0/24 prefix before any inbound policies?

  • 1
    I am posting this as a comment because I don't have a link to an official Cisco document stating this, but you can't. I don't think that can be accepted as an answer without a link to something on cisco.com, I can't find anything but I'm certain that you can't, however my word isn't really good enough. – jwbensley Feb 16 '16 at 20:00
  • Did any answer help you? if so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you could provide and accept your own answer. – Ron Maupin Aug 12 '17 at 4:19
3

I believe this is not possible as @jwbensley said. Though it's also unlikely that cisco.com explicitly says that this functionality isn't implemented.

When you're viewing attributes such as community you're looking at BGP table. Route is getting into BGP table after policy has been applied. So if you change attributes with policy, you can only see modified attributes.

0

If you turn on inbound soft-reconfiguration on the neighbor in question, then you will see another entry in the list with the pre-policy communities on it.

-1
show ip bgp <prefix> 

R2_#sh ip bgp 77.77.77.0
BGP routing table entry for 77.77.77.0/24, version 11
Paths: (2 available, best #1, table default)
  Advertised to update-groups:
     15        
  Refresh Epoch 1
  **65055 65077**
    5.5.5.1 from 10.60.70.2 (33.33.33.1)
      Origin IGP, metric 0, localpref 100, valid, internal, af-export(2), best
      Community: 65070:65072
      rx pathid: 0, tx pathid: 0x0
  Refresh Epoch 1
  **65055 65077**, (received-only)
    5.5.5.1 from 10.60.70.2 (33.33.33.1)
      Origin IGP, metric 0, localpref 100, valid, internal
      rx pathid: 0, tx pathid: 0
R2_#

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.