11-02-2012 03:11 AM - edited 03-07-2019 09:49 AM
Hi,
We recently experienced that our VPC peer-keepalives are not working as we expected it to be.
Last Tuesday we saw that between 2 Nexus 7000 switches the VPC peer-keepalive was not working. On one switch we saw that it stated that the link was alive, while on the other switch we saw that the link was not alive.
After shutting down both interfaces, the link was restored.
We then searched in the log when this problem had occured, and we saw numerous entries with the following text:
2012 Nov 2 07:17:47.718391 CO-DERB-02-V01 %VPC-6-PEER_KEEP_ALIVE_RECV_INT_LATEST: In domain 2, VPC peer-keepalive received on interface Eth1/48
2012 Nov 2 07:17:47.718450 CO-DERB-02-V01 %VPC-2-PEER_KEEP_ALIVE_RECV_FAIL: In domain 2, VPC peer keep-alive receive has failed
2012 Nov 2 07:17:47.975636 CO-DERB-02-V01 %VPC-6-PEER_KEEP_ALIVE_RECV_INT_LATEST: In domain 2, VPC peer-keepalive received on interface Eth1/48
2012 Nov 2 07:17:47.975688 CO-DERB-02-V01 %VPC-6-PEER_KEEP_ALIVE_RECV_SUCCESS: In domain 2, vPC peer keep-alive receive is successful
We also saw these entries on a other Nexus 7000 pair in a other datacenter of ours.
We are using NX-OS 5.0.3, but are currently in a upgrade process. We could not find a similar bug in the Cisco BugToolkit, so we are wondering what could cause this. The N7K's are connected via one UTP wire that uses Ethernet1/48 (1 gig link) on both switches. Both switchports have similar configuration, but with a different IP address.
Here is the configuration for our VPC keep-alive:
interface Ethernet1/48
vrf member vPC_keep
ip address 172.20.252.5/30
no shutdown
--------------------------------------------------------------------------------
Port Name Status Vlan Duplex Speed Type
--------------------------------------------------------------------------------
Eth1/48 vpc keep alive t.b connected routed full 1000 10/100/1000
vpc domain 2
peer-switch
role priority 8192
peer-keepalive destination 172.20.252.6 source 172.20.252.5 vrf vPC_keep interval 500 timeout 3
delay restore 180
peer-gateway
reload restore
track 10
Many thanks in advance!
Solved! Go to Solution.
11-02-2012 05:52 AM
Hi,
can you do a "sh vpc stat peer-kee"? to see how many times the state has changed?
You VPC may be flapping because of the interval 500 timeout 3.
Can you change these to default and test again?
HTH
11-02-2012 05:52 AM
Hi,
can you do a "sh vpc stat peer-kee"? to see how many times the state has changed?
You VPC may be flapping because of the interval 500 timeout 3.
Can you change these to default and test again?
HTH
11-02-2012 06:03 AM
Hi,
Thanks for responding so quickly.
On one pair of N7K, I see as much as 900 state changes. I think you're right with the interval 500 timeout 3. I'll going to tweak this and get back to you.
11-02-2012 10:57 AM
Also, keep this in mined if you are planning to upgrade the OS
Beginning with Cisco NX-OS Release 5.2(1), the reload restore command and method is deprecated. We recommend that you use the auto-recovery command and method.
HTH
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