Manual Switchover is VSS - Rebooting Switch 1 complete

[abhisar patil]

Dear Team,

I have configured the VSS and doing the testing. Presently switch 1 is active and switch 2 standby and I am connected on one of the port on switch1 module 1. I entered redundancy force-switchover command and it rebooted whole switch and not the sup and I got disconnected from the switch and it took some time to come up the switch 1.

So I want only sup to switch not the switch, what is the command to test? Any other comment?

Thank You,

[Bilal Nawaz · Accepted solution]

Hello, I have never encountered another command whereby a manual failover will keep both chassis up and running during or after switchover with the control-plane role switching between the pair. I think this is only command to manually failover.... and restart of the switch behaviour is/should be expected.

VSS Specific Convergence

Active Switch Failover

An active failover is initiated by one of the following actions:

•Application of the redundancy force-failover command

•Physically removing an active supervisor from service

•Powering down an active supervisor

The convergence remains the same for any of the above methods of active failover. The process of switching over from one VSS switch member to the other (active to hot-standby) is influenced by many concepts and design considerations discussed in the preceding sections. The following sequence of events provide a summary of the failover convergence process:

1. Switchover is invoked via software CLI, removing supervisor, powering down active switch, or system initiation.

2. The active switch relinquishes the unified control plane; the hot-standby initializes the SSO control plane.

3. All the line cards associated with active switch are deactivated as the active chassis reboots.

4. Meanwhile, the new active switch (previous hot-standby switch) restarts the routing protocol and starts the NSF recovery process.

5. In parallel, the core and access-layer rehash the traffic flow depending on the topology. The unicast traffic is directed toward the new active switch, which uses a hardware CEF table to forward traffic. Multicast traffic follows the topology design and either rebuilds the multicast control plane or uses the MMLS hardware table to forward traffic.

6. The NSF and SSO functions become fully initialized, start learning routing information from the neighboring devices, and update the forwarding and control plane protocols tables as needed.

http://www.cisco.com/c/en/us/td/docs/solutions/Enterprise/Campus/VSS30dg/campusVSS_DG/VSS-dg_ch4.html#wp1081762

hth

Bilal - CCIE #45032

[abhisar patil]

Dear All,

Thank you for the clarifications. So it means by any how, if active sup have any issues and switchover happens it will reboot the switch including modules and will be up when switch comes back online(Not necessary Sup should also come back).

Thank You,

Abhisar.

[Bilal Nawaz]

Hi Abhisar

yes this is correct.

hope this helps

[Aabed Khalifa]

Hello Abhisar ,

I believe what you are aiming is a typical scenario of a Quad-SUP design , where you have to install 2 SUP's per chasse , and this is where a soft fail-over can be performed without box reload .

BR,

A K