[c-nsp] BGP line prioritization

[Pete Templin]

Dracul wrote:
> Hi all, I am using two links for BGP. is there a way I can do preference to
> use the other line first? Let's say I prefer neighbor yyyy
> what config should I add below? Thanks!

Outbound traffic (inbound announcements):
How aggressively do you want to prefer neighbor yyy?
A lot: use idea 1
A little: use idea 2

Inbound traffic (outbound announcements):
How aggressively and predictably do you want to prefer yyy?
A lot: use idea 3 (you'll have to integrate with existing RM)
A little: use idea 4  (you'll have to integrate with existing RM)


idea 1:
route-map yyy-high-pref-in p 10
  set local 200
!
router bgp xxxx
  neig 124.xxx.xxx.xxx route-map yyy-high-pref-in in
!
end

idea 2:
route-map xxx-prepend1-in p 10
  set as prep xxx !(their AS)
!
router bgp xxxx
  neig 123.xxx.xxx.xxx route-map xxx-prepend1-in in
!
end

idea 3:
Contact provider xxx and find out the community to request low ("peer 
backup") local preference in their network.  Assume x:y.

route-map xxx-low-pref p 10
set commu x:y
!
router bgp xxx
neig 123.xxx.xxx.xxx send-community
neig 123.xxx.xxx.xxx route-map xxx-low-pref out
!
end

idea 4:
route-map xxx-prepend1-out p 10
  set as prep xxx !(your AS)
!
router bgp xxx
  neig 123.xxx.xxx.xxx route-map xxx-prepend1-out out
!
end