Remove BGP no-export community

[msizi.mthembu]

Hello,

I have a prefix that I learn from another AS1, which I set a "no-export" community inbound to AS2. AS2 has eBGP sessions to AS3 and AS4. I need to remove/override the "no-export" outbound to AS4 only. I tried the below policy but the prefix is still not being advertised out to AS4. Kindly advise

route-policy POLICY-OUT-1
  if destination in ADVERTISE-OUT then
    delete community in (no-export)
    pass
  else
    drop
  endif
end-policy
 

Thanks,

Msizi

[pman]

Hi,

maybe this will help you:

delete community in (internet, no-export, no-advertise, local- as, *:*)

https://www.cisco.com/c/en/us/td/docs/routers/asr9000/software/asr9k_r5-3/routing/command/reference/b-routing-cr53xasr9k/b-routing-cr53xasr9k_chapter_01010.html#wp1729919867

[Harold Ritter]

Hi @msizi.mthembu ,

Applying the route-policy outbound on the neighbor to AS3 and AS4 will not work. The updates will not be sent to these neighbors because they are tagged with no-export and would therefore never make it through the route-policy. If you have two routers in AS2 (connected via iBGP), you could apply the route-policy inbound on the second router. This would definitely work.

Regards, 

[nabs]

Hi @Harold Ritter ,

Hope you are doing well.
Is it the same in an MPLS backbone with MP iBGP ?
I mean, if i want to remove "no-export" community only on vrf A and not on vrf B (that are in a same PE) , Does i have to configure an import-map on vrf A with the route-policy shared by @msizi.mthembu ? or I must do it on the PE (that hosts vrf A and vrf B) in inband direction, so on the MP iBGP sesssion with route reflector ?

[Harold Ritter]

Hi @nabs ,

The original post dates and your case is different from it. Can you please ask a new question and provided the information specific to you issue?

[paul driver]

Hello

---

@msizi.mthembu wrote:

Hello,

I have a prefix that I learn from another AS1, which I set a "no-export" community inbound to AS2. AS2 has eBGP sessions to AS3 and AS4. I need to remove/override the "no-export" outbound to AS4 only.

---

Most simplistic way would be to NOT send/advertise community towards AS4, this should then strip any community attribute in the bgp update

Another way would to be apply an community attribute of INTERNET ingress from AS1