Cisco SD WAN OSPF - LAN SWITCH NOT INSTALLING LEARNED ROUTES

[ArielGustavoHerediaOliva72399]

Hi all, 

I'm running a 20.9 sd wan home lab with Cloud vEdges, I have a dual site (one of 4) with OSPF running on the LAN side where I have a L3 switch doing as a core.

I have 3 VPNs (100, 300, 400) which are mapped to respective ospf process with vrf in the core (100 vrf 100, 300 vrf 300 and 400 vrf 400). 

The issue I'm running into is that Core switch has all the routes redistributed from OMP in its database for each VPN/VRF, but it's ignoring all those routes due the DN-bit set by the vedges which it's used for loop prevention:

*Apr 30 03:04:57.322: OSPF-100 EXTER: Start processing AS External LSA 5/10.1.99.12/10.10.20.22, mask 255.255.255.252
*Apr 30 03:04:57.322: OSPF-100 EXTER: age 12, seq 0x80000005, metric 16777214, metric-type 2, fw-addr 0.0.0.0
*Apr 30 03:04:57.322: OSPF-100 EXTER: Downward bit set, ignoring the LSA

When I move one peering, let's say VPN100 on vEdge to peer with ospf in the GRT, everything works fine, the issue only happens when using ospf with vrf instances.

What should I do to get this working with per OSPF and VRF on the core switch? 

Any idea would be helpful, thanks!

[Harold Ritter · Accepted solution]

Hi @ArielGustavoHerediaOliva72399 ,

You need to configure "capability vrf-lite" under the ospf process on the core switch.

Regards,

[Kanan Huseynli · Accepted solution]

Hi,

OSPF process with VRF assumes itself connected to OSPF MPLS Superbackbone i.e PE router where DN-bit based LSAs are ignored. You need "capabilty-vrf" to disable that logic.

[ArielGustavoHerediaOliva72399]

Hi @Harold Ritter and @Kanan Huseynli, 

Everything is working smoothly now.

Thank you for your help!

[Harold Ritter]

You are very welcome @ArielGustavoHerediaOliva72399 and thanks for the feedback