HSRP-5-STATECHANGE (Hot Standby Routing Protocol) change state from standby to active

[GiampaoloDiGiorgio1521]

Dear All

Could someone explain to me what happened to my catalyst 4500, please?

Aug 19 15:32:28 10.12.1.2 15467: 015463: Aug 19 11:32:27.980 UTC: %HSRP-5-STATECHANGE: Vlan1 Grp 1 state Standby -> Active
Aug 19 15:32:31 10.12.1.2 15468: 015464: Aug 19 11:32:30.980 UTC: %EC-5-UNBUNDLE: Interface Te1/2 left the port-channel Po1
Aug 19 15:32:32 10.12.1.2 15469: 015465: Aug 19 11:32:30.992 UTC: %EC-5-UNBUNDLE: Interface Te1/1 left the port-channel Po1
Aug 19 15:32:32 10.12.1.2 15470: 015466: Aug 19 11:32:31.988 UTC: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/2, changed state to down
Aug 19 15:32:32 10.12.1.2 15471: 015467: Aug 19 11:32:31.988 UTC: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet1/1, changed state to down
Aug 19 15:32:32 10.12.1.2 15472: 015468: Aug 19 11:32:31.988 UTC: %LINEPROTO-5-UPDOWN: Line protocol on Interface Port-channel1, changed state to down
Aug 19 15:32:33 10.12.1.2 15473: 015469: Aug 19 11:32:32.996 UTC: %LINK-3-UPDOWN: Interface TenGigabitEthernet1/2, changed state to down
Aug 19 15:32:34 10.12.1.2 15474: 015470: Aug 19 11:32:32.996 UTC: %LINK-3-UPDOWN: Interface Port-channel1, changed state to down
Aug 19 15:32:34 10.12.1.2 15475: 015471: Aug 19 11:32:32.996 UTC: %LINK-3-UPDOWN: Interface TenGigabitEthernet1/1, changed state to down
Aug 19 15:33:01 10.12.61.73 2571: Aug 19 13:33:01.619 CET: %SW_MATM-4-MACFLAP_NOTIF: Host 0003.e193.6d90 in vlan 1 is flapping between port Fa1/1 and port Gi1/1
Aug 19 15:33:01 10.12.61.224 257: Aug 19 13:33:01.652 CET: %SW_MATM-4-MACFLAP_NOTIF: Host 0003.e191.19d9 in vlan 1 is flapping between port Gi1/1 and port Fa1/2

[marce1000]

 - The obvious would be to check the involved connections for their correctness and 'physical stability'.

 M.

[Giuseppe Larosa]

Hello Giampaolo,

the root cause should be the failure of the bundle Po1.

This breaks connectivity in Vlan 1, the local switch does not listen anymore to HSRP Hellos from current active device and after three failures in a row it takes over declaring to be the new HSRP active for the group in Vlan 1.

>> Aug 19 15:32:31 10.12.1.2 15468: 015464: Aug 19 11:32:30.980 UTC: %EC-5-UNBUNDLE: Interface Te1/2 left the port-channel Po1
Aug 19 15:32:32 10.12.1.2 15469: 015465: Aug 19 11:32:30.992 UTC: %EC-5-UNBUNDLE: Interface Te1/1 left the port-channel Po1

If using LACP or PAGP the reason for unbundling can be that the local switch stopped to receive LACP / PAGP messages on the member links and then turns them down.

You should investigate what is happening on the companion switch of this C4500.

Hope to help

Giuseppe

[GiampaoloDiGiorgio1521]

Dear Giuseppe

I checked switches configuration and I think both have wrong HSRP Configuration

If one switch fail there is no Major Priority, it means must be change in:

Standby 1 Priority 110 (for Primary)

Standby 1 Priority 100 (for Secondary)

Could you please let me know if my studies are right?

Sincerely

[Giuseppe Larosa · Accepted solution]

Hello Giampaolo,

your understanding is correct.

However, if you are using tracking of the uplink interface with default settings when failing the priority is reduced by 10.

so it would be better to have a difference of 5

pri 105 on primary pri 100 on secondary

+

pre-empt to allow to take over when priority is lower

+

tracking of the uplink

if the HSRP priority is the same I think the router with the higher IP address should be active (or the opposite the router with the lower IP address)

HSRP should have a rule for cases of same priority values. This should not be the root cause of your issues.

However, pre-emption can occur only if priorities are different see

https://community.cisco.com/t5/switching/hsrp-election/td-p/1919665

so in your case, what happens is that first switch to come up should be the Active HSRP router.

It is better to use different priorities so that active role is a deterministic choice.

Hope to help

Giuseppe