[c-nsp] default RT filter behaviour on XR

[Adam Vitkovsky]

Hi Folks,
During the weekend we ran into an interesting bahaviour of BGP default RT
filter on a9k. 
We connected a new PE into vpnv4 feeds and after a while the max-route limit
shut down the vpnv4 sessions -meaning the PE acted like a vpnv4
route-reflector receiving all vpnv4 routes. 
My colleague tested it in the lab next morning and what it turned out to be
was that in BGP config on the new PE there was an unused neighbor-group with
a vpnv4 afi and route-reflector-client cmd. 

I would think that unless the neighbor-group is not yet used on any peer it
should not make the router to turn off the default rt-filter. 
This was on 4.2.3
 

adam