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.

Regards,

[balaji.bandi]

To understand the problem better, can you post the HLD and how interface connected and full config of both the switches ?

[abimadaro4462]

Hello,

Here's the HLD

Here's the configuration;

SW 1

------

vpc domain 10
peer-switch
peer-keepalive destination 10.10.10.2 source 10.10.10.1 vrf vpcvrf
peer-gateway
layer3 peer-router

interface Vlan1
no ip redirects
no ipv6 redirects

interface Vlan172
no shutdown
no ip redirects
ip address 172.16.8.5/29
no ipv6 redirects
ip ospf dead-interval 40
ip router ospf 1 area 0.0.0.0

interface port-channel1
switchport mode trunk
spanning-tree port type network
vpc peer-link

interface port-channel10
switchport mode trunk
switchport trunk allowed vlan 172
vpc 10

interface Ethernet1/1
no switchport
vrf member vpcvrf
ip address 10.10.10.1/30
no shutdown

interface Ethernet1/2
switchport mode trunk
channel-group 1 mode active

interface Ethernet1/3
switchport mode trunk
channel-group 1 mode active

interface Ethernet1/4
switchport mode trunk
switchport trunk allowed vlan 172
channel-group 10

router ospf 1
router-id 10.10.10.1

SW2

-----

vpc domain 10
peer-switch
peer-keepalive destination 10.10.10.1 source 10.10.10.2 vrf vpcvrf
peer-gateway
layer3 peer-router

interface Vlan1
no ip redirects
no ipv6 redirects

interface Vlan172
no shutdown
no ip redirects
ip address 172.16.8.4/29
no ipv6 redirects
ip ospf dead-interval 40
ip router ospf 1 area 0.0.0.0

interface port-channel1
switchport mode trunk
spanning-tree port type network
vpc peer-link

interface port-channel10
switchport mode trunk
switchport trunk allowed vlan 172
vpc 10

interface Ethernet1/1
no switchport
vrf member vpcvrf
ip address 10.10.10.2/30
no shutdown

interface Ethernet1/2
switchport mode trunk
channel-group 1 mode active

interface Ethernet1/3
switchport mode trunk
channel-group 1 mode active

interface Ethernet1/4
switchport mode trunk
switchport trunk allowed vlan 172
channel-group 10

router ospf 1
router-id 10.10.10.2

Here's the output of show ip ospf neighbor

Neighbor ID Pri State Up Time Address Interface
10.10.10.1 1 FULL/DR 08:49:38 172.16.8.5 Vlan172
10.20.10.10 1 EXSTART/DROTHER 00:00:01 172.16.8.1 Vlan172

I have deleted the HSRP configuration for testing but same results.

[paul driver]

Duplicate post  - here