VSS 1440 vs STP+HSRP for highest core availability

[servicedesk]

For the highest availability, how does two VSS pairs (2x2 Cat 6500s, 4 in total) compare to a ring of 4x cat 6500's using STP and HSRP? I'm nervous about using VSS to turn our two core data centre switches into one single point of failure - the VSS console / software.

[yassine-m]

Each VSS system is composed of 2 Cat 6500 managed as one unit, VSS ensure a permanent layer 2 connectiviy between the two catalyst. So this solution bring a full redundancy by eliminating SPOF.

[servicedesk]

But if the two 6500s aren't configured as a VSS pair, and use STP+HSRP for the dual-connected server, iSCSI SAN hosts, and access layer switches, there's also no single point of failure. My concern is that the VSS system/protocol itself is newer, less known, and possibly more complex than STP. Essentially it boils down to a single mechanism to take care of the fail-over ... and I'm thinking I trust STP more than VSS!

[Edison Ortiz]

Then I suggest contacting your Cisco SE and have a run on a VSS pair in your Lab until you feel comfortable.

Think of the VSS design as running a stackable 3750 vs 3560 with uplink ports.