[c-nsp] BGP session resets if NLRI exchanged

[Paul Cosgrove]

We are attempting to establish a new BGP session between one of our 
CRS-1 routers, and a Redback SE800 router owned by another provider.  Am 
not familiar with Redbacks myself and we have not peered with any before 
(as far as we know anyway).  The BGP session only remains up if no NLRI 
is exchanged.  If the other provider sends any prefixes to us we reply 
with a "invalid length for attribute" notification; if we send any 
prefixes to them they reply with  "invalid or corrupt AS path". 

The other provider uses VPNv4 within their network, though I understand 
that it is not configured on this peering.  I'm wondering whether these 
errors could result if their router expects a RD (and sends one) on the 
advertisements, perhaps due to a software bug or typo in the config. 

Perhaps someone has seen this problem before?

Paul.