Installing backup bgp route in PE router / IOSXR 7.4.2

[shreerampardhy]

hi All,

looking for ideas on how to achive following - 

On my local PE router ( VRF A ), i have cutomer route being received from my remote PE. The local PE  VRF A is also receiving the same route via an external BGP neighbour ( via a longer AS path ). 

Only one route is being offered to the vrfs routing table ( currently MPLS learnt route is being used as best route ). I wanted to have the external route also offered to the routing table as a backup route. Any ideas how to achieve that?

Following is  what i have tried so far. Didnt work.

route-policy BACKUP
set path-selection backup 1 install
end-policy
!
router bgp 1
address-family ipv4 unicast
additional-paths selection route-policy BACKUP
!
address-family vpnv4 unicast
export to vrf allow backup
additional-paths selection route-policy BACKUP
!
vrf A
rd 1:1
bgp bestpath as-path multipath-relax
address-family ipv4 unicast
maximum-paths eibgp 2
label mode per-ce
additional-paths selection route-policy BACKUP

I had change the label mode to per-ce because one of the Cisco link mentioned following (https://xrdocs.io/ncs5500/tutorials/ncs5500-routing-in-vrf/) - 

Per-CE (resilient)

Single label allocated by CE, whatever number of prefixes, improved scale
EIBGP multipath, PIC is supported, single Label lookup

[shreerampardhy]

hi ALl,

Forgot to mention. I want to ensure that i use Path2 only when path1 goes down. I want Path2 to act as backup only. It should not be used when Path1 is available.

[shreerampardhy · Accepted solution]

Useful for anyone who might have similar issue. 

I was able to fix this with following configuration - 

router bgp 1
vrf A
rd 1:1
bgp bestpath as-path multipath-relax
address-family ipv4 unicast
maximum-paths eibgp 2
label mode per-ce
additional-paths selection route-policy BACKUP

route-policy BACKUP
set path-selection backup 1 install
end-policy
!

The problem was that i was having SR TE tunnels enabled. Cicso documentation says that BGP PIC feature will not work with SR TE. I had to disable my TE tunnel to get this working.