Cisco StackWise vs VSS vs StackWise Virtual: Full Comparison

VSS, StackWise and StackWise Virtual are Cisco's three answers to "make several switches behave like one", and even experienced engineers mix them up. The core distinctions: StackWise is a proprietary-cable stack for fixed switches in one closet, VSS virtualizes two chassis over conventional 10GE ports, and StackWise Virtual is essentially VSS reborn on the Catalyst 9000 generation — same concept, different OS and platforms. This guide, distilled from the Cisco Community thread on the topic, gives you a clean comparison table plus platform support facts.

The Three Technologies Defined

VSS (Virtual Switching System)

VSS combines a pair of chassis (Catalyst 6500/6800, 4500) into one logical switch using conventional 1G/10G ports as the Virtual Switch Link. It supports geographic separation and is designed for core/distribution where deterministic sub-second failover matters.

StackWise

StackWise unites up to 8 switches (Catalyst 9300 with StackWise-480; up to 9 on older 3750 generations) using proprietary stacking modules and cables, so it is confined to a single wiring closet. The 9300 stack tops out at 8 members; the 9300L uses StackWise-320.

StackWise Virtual

StackWise Virtual (SVL) is VSS for the Catalyst 9000 era: two switches virtualized over conventional fiber links, allowing long-distance distribution. It is supported on Catalyst 9400/9500/9600 (and 3850), not on Catalyst 9200/9300 — those only support physical StackWise. VSS and SVL are functionally the same thing; the difference is the OS (classic IOS vs IOS-XE) and marketing.

Quick Comparison Table

Nexus switches use a different, vPC-based model — see our Nexus vPC failover troubleshooting article. For the 9300-specific angle, read Catalyst 9300 StackWise vs VSS.

Which One Should You Pick?

For access-layer port density in a single closet, StackWise is simpler and cheaper. For core or distribution redundancy where a second of downtime is expensive, VSS or StackWise Virtual provides stateful switchover over fiber. The deciding factors are platform support (9300 cannot run SVL) and whether the two units are in the same closet or geographically separate.

Related Reading

Pair this with Catalyst 9300 StackWise vs VSS and Cisco Nexus vPC failover troubleshooting for the complete virtualization picture across Catalyst and Nexus families.

原文链接：https://community.cisco.com/t5/switching/vss-cisco-stackwise-and-cisco-stackwise-virtual/td-p/3932795