[c-nsp] Segment Routing & BGP Prefix-SID

Arthur Liew arthurliew80 at gmail.com
Sat May 20 00:03:02 EDT 2017

Hi Folks,

Hey there ! I'm just watching the Ciscolive video on their Cisco Agile
Carrier Ethernet

BRKSPG-2518 Cisco EPN Carrier Ethernet and Mobile Backhaul Architecture

Have anyone deployed and tested on IOS-XRv?

I'm trying on the idea of Cisco ACE with BGP LU (Prefix-SID), with the same
label index to IGP, but BGP still allocates its own label range (24000

Second idea touted by Cisco is the BGP Prefix-SID persistence, where same
IGP label is propagated into BGP and persist across the network, but the
problem is doesn't the label change every time we change the next-hop-self
at the ABR in the BGP-LU setup?

RP/0/0/CPU0:XRv-1#sh bgp labels

Origin codes: i - IGP, e - EGP, ? - incomplete
   Network            Next Hop        Rcvd Label      Local Label
*>         nolabel         3
*>i10.0.0.2/32        3               24005
*>i10.0.0.3/32        3               24004
*>i10.0.0.4/32        24001           24006
*>i10.0.0.5/32        24004           24007
*>i10.0.0.6/32        24006           24008

Anyone facing similar problems testing out the idea? Appreciate sharing
from anyone playing with the idea or have implemented the Cisco ACE

Cheers !


mpls ldp
segment-routing global-block 16000 23999
route-policy SID($SID)
 set label-index $SID
router bgp 9534
 address-family ipv4 unicast
  network route-policy SID(1)
router isis core
 address-family ipv4 unicast
  segment-routing mpls sr-prefer
 interface Loopback0
  address-family ipv4 unicast
   prefix-sid index 1

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