[ixpmanager] Bird BGP Message

[Nick Hilliard (INEX)]

Shahab Vahabzadeh wrote on 25/11/2020 06:16:
> Dear All,
> All our customers get these two types of messages in their cisco routers 
> log, And as its repeating a lot its bothering them. Do you have any idea 
> what kind of config in bird is not matching Cisco configuration?
> 
> %BGP-6-MALFORMEDATTR: Malformed optional transitive attribute in (BGP(0) 
> Prefixes: 81.12.43.0/24 <http://81.12.43.0/24> ) received from RS1
> %BGP-6-MSGDUMP_LIMIT: unsupported or mal-formatted message received from RS1
> 
> They are getting lots of these messages for different prefixes from 
> both route servers. Also They are not getting this message only for v4 
> prefixes they are getting it for v6 prefixes in v6 route servers too.

Probably it's a large bgp community.  What attributes is 81.12.43.0/24 
announced with?  You can check this using:

# birdc -s <socket> show route 81.12.43.0/24 all

If this is caused by a large community, then router customers will need 
to upgrade their routers to get rid of the message.  You can check which 
router software versions support LCs on:

http://largebgpcommunities.net/implementations/

Nick