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Beginner

Intra-AS Option B between XR unreachable (no label found)

Hi, 

I'm trying to set-up bgp vpnv4 between different AS:

Cust_Site_A-->AS10-->AS11-->AS12-->Cust_SIte_B

 

  • Between AS10 and AS11 it's Inter-AS option C (Labeled-unicast between the ASBRs, and VPNv4 between the RRs)
    • I'm receiving Cust_Site_A prefixes with next hop of AS10's route reflectors
  • Between AS11 and AS12 it's Inter-AS option B (direct vpnv4)

For some reason:

AS11 is not advertising the VPNv4 prefixes (the one received from AS10's RR) to AS12. BGP debugs show the below messages:

=============================================================

bgp[1051]: [default-upd] (vpn4u): <UPDLABEL>: tbl=TBL:default (1/128), afi=4: ug=0.3, sg=0.2, ugfl=0x00004023: net=2ASN:2:2:10.10.10.10/32, PELEM=11c52f68(lpathid=1, fl=0x00000001), PATH=11c32f38(12.12.12.12/32,12.12.12.12,0, 0x4000000025060001), reflected=0, bmsgfl=0x00000000, wdr=0::: netlab=0/0, pathlab=24014, updlab=1048577(0x00100001)

--------------------------------------------------------------------------
bgp[1051]: [default-upd] (vpn4u): No unreachable (no label found) sent to sub-group 0.2 (Regular) with 2ASN:2:2:10.10.10.10/32 - already withdrawn

===============================================================

If i use next-hop-unchaed on AS 11 towards AS12, the prefixes get advertised to AS12 with next-hop of AS10's RR (which of course AS12 cannot use).

If I removed next-hop-unchanged, the prefixes get withdrawn, with below logs:

===============================================================

 bgp[1051]: [default-upd] (vpn4u): <UPDLABEL>: tbl=TBL:default (1/128), afi=4: ug=0.3, sg=0.3, ugfl=0x00004023: net=2ASN:2:2:10.10.10.10/32, PELEM=11c52f68(lpathid=1, fl=0x00000001), PATH=11c32f38(12.12.12.12/32,12.12.12.12,0, 0x4000000025060001), reflected=0, bmsgfl=0x00000000, wdr=1::: netlab=0/0, pathlab=24014, updlab=524288(0x00080000)

--------------------------------------------------------------------------
bgp[1051]: [default-upd] (vpn4u): Created withdraw message 0x111085d0, for filtergroup 0.2

--------------------------------------------------------------------------
 bgp[1051]: [default-upd] (vpn4u): Created msg elem 0x111b9044 (pointing to message 0x111085d0), for filtergroup 0.2

--------------------------------------------------------------------------
bgp[1051]: [default-upd] (vpn4u): Sending UPDATE (creating new msg) to sub-group 0.3 (Regular) pelem (Regular) filter-group0.2 with 2ASN:2:2:10.10.10.10/32 (changedfl=0x0/0x0, bmsgflags=0x00000000, originator 0.0.0.0) unreachable (no label found)

===============================================================

Not sure what the issue is! I'm using a vanilla config as per Cisco's config guid for Option B.