VS-C6509E-S720-10G (VSS chassis)

pcce5w2hlh · ‎04-22-2010

I understand that redundant supervisor is not required in running VSS in the C6500 series chassis. (i.e. 1 sup engine per chassis, for the two chassis interlinking with 10GE).

What would happen if the sup engine in one of the chassis fails? If there are additional modules (e.g. WS-X6548-GE-45AF) in the failed chassis, would the modules under the failed VSS chassis be powered down too?

Jon Marshall · ‎04-23-2010

tanhongbak wrote:

I understand that redundant supervisor is not required in running VSS in the C6500 series chassis. (i.e. 1 sup engine per chassis, for the two chassis interlinking with 10GE).

What would happen if the sup engine in one of the chassis fails? If there are additional modules (e.g. WS-X6548-GE-45AF) in the failed chassis, would the modules under the failed VSS chassis be powered down too?

It's not so much that it is not required, it is not yet supported although Cisco have said redundant supervisors in the same chassis with VSS will be supported in the future.

If the supervisor fails then the modules in that chassis are not available to be used because the VSL link is not operational. Until the supervisor has recovered the modules in that chassis cannot be used. Note that this applies to both the active and standby supervisor status, the only difference being if the active supervisor fails then a failover is needed.

Jon

pcce5w2hlh · ‎04-23-2010

For VSS concept, isn't there a single point of failure at the sup engine at either chassis if failed? It just seems that if the sup engine fails, the brain is died, and the entire chassis together with the rest of the modules, within that chassis, are useless until the sup engine recovers.

That is a real drawback of using VSS?

Jon Marshall · ‎04-23-2010

tanhongbak wrote:

For VSS concept, isn't there a single point of failure at the sup engine at either chassis if failed? It just seems that if the sup engine fails, the brain is died, and the entire chassis together with the rest of the modules, within that chassis, are useless until the sup engine recovers.

That is a real drawback of using VSS?

Yes but the idea is you never single hone any end device such as a server to just one of the chassis. So VSS should be used primarily for switch uplink and servers both of which can be connected to both chassis using MEC (Multichassis etherchannel) anf then if one supervisor fails there should be no interruption of packet forwardng because of MEC.

Jon