ospf stub area router thinking it is a ABR when using vrf

[philipheppe]

I have configured ospf using a vrf.

The area configured as stub no-summary and no other area's.

In ospf vrf database there are 0.0.0.0 summary routes but the are not inject into routing table.

show ospf vrf X give strange result is say "it is an area border router" and later on Number of areas in this router is 1. 0 normal 1 stub 0 nssa

Anybody give me the hint.  (I'm using ios-xr 4.1.1)

VRF v200 in Routing Process "ospf core" with ID X

NSR (Non-stop routing) is Disabled

Supports only single TOS(TOS0) routes

Supports opaque LSA

It is an area border router

Router is not originating router-LSAs with maximum metric

Initial SPF schedule delay 50 msecs

Minimum hold time between two consecutive SPFs 200 msecs

Maximum wait time between two consecutive SPFs 5000 msecs

Initial LSA throttle delay 50 msecs

Minimum hold time for LSA throttle 200 msecs

Maximum wait time for LSA throttle 5000 msecs

Minimum LSA interval 200 msecs. Minimum LSA arrival 100 msecs

LSA refresh interval 1800 seconds

Flood pacing interval 33 msecs. Retransmission pacing interval 66 msecs

Adjacency stagger enabled; initial (per area): 2, maximum: 64

    Number of neighbors forming: 0, 1 full

Maximum number of configured interfaces 1024

Number of external LSA 0. Checksum Sum 00000000

Number of opaque AS LSA 0. Checksum Sum 00000000

Number of DCbitless external and opaque AS LSA 0

Number of DoNotAge external and opaque AS LSA 0

Number of areas in this router is 1. 0 normal 1 stub 0 nssa

[philipheppe]

complement post:

This is excact the same behavior as on ios but there i can use the command:

capability vrf-lite

But it's not available on ios-xr.   command capability

disable-dn-bit-check

looks the same, but i didn't bgp etc so the bit is never set.

[Alexei Kiritchenko · Accepted solution]

Hello Philip,

The reason why ASR9k considers itself as ABR is the fact that the OSPF instance is associated with a non-default VRF, which means ASR9k is a PE and PE is an ABR by definition - assumption is that PE is connected to a  VPN backbone.

As i undersdood we don't have a VPN backbone here, but XR does not support complete vrf-lite and hence there is no similar command as in IOS and the default (and any summary LSA) is not installed.

There is a feature request for this:

CSCtr78311   OSPFv2: Implement full VRF-lite capability in IOS-XR

It is expected to be in 4.3.0.

Regards,

/A