vPC & OSPF

[abimadaro4462]

Hello,

I have the following scenario, two nexus 9K are configured as vPC peers with HSRP, the upstream is connected to active/standby firewall with OSPF configured.

below is the configuration;

SW1 & SW2

----

router ospf 1
bfd
router-id 10.10.10.4
area 0.0.0.4 nssa no-summary

interface Vlan20
ip ospf dead-interval 3
ip ospf hello-interval 1
ip ospf network point-to-point
ip router ospf 1 area 0.0.0.4
ip ospf bfd

interface Vlan20
hsrp 20
ip 20.20.20.1

vpc domain 10
peer-switch
role priority 100
peer-keepalive destination 10.10.10.2 source 10.10.10.1 vrf vpcvrf
peer-gateway
layer3 peer-router
auto-recovery
ip arp synchronize

interface port-channel1
vpc peer-link

Switch one neighbor is flapping between EXSTART and EXCHANG

Neighbor ID Pri State Up Time Address Interface
10.10.10.5 1 FULL/ - 00:25:17 20.20.20.3 Vlan20
10.20.10.10 1 EXCHANGE/ - 0.065025 20.20.20.6 Vlan20

Please advice if the above configuration is correct.

[paul driver]

Hello

Are you running 9Ks?

[abimadaro4462]

Hello,
Yes I'm running 9Ks.

[paul driver]

Hello

well then it seems L3 over vPC is now applicable however I would suggest if you can to have a separate L3 for you backup path between switches instead of using the and svi over peer-link

[abimadaro4462]

Hello,
Thanks, I figured out what is the problem, I was trying to configure the OSPF network type as point to point while it should be in broadcast mode.

[pille1234 · Accepted solution]

You are right, your setup is valid and supported assuming you have the required minimum software version on the N9K.

However within your vlan20 you have 3 OSPF neighbors so this is obviously no P2P network. As such the "ip ospf network point-to-point" configuration needs to be removed.

And you don't need hsrp there, it is just cluttering your configuration.

[abimadaro4462]

Hello,
Thanks, this is correct, the network in this case should be broadcast not P2P.

Regards,