StackWise Virtual
This is a MLAG technology.
Used to reduce complexity from FHRP and STP.
Images courtesy of Cisco.
Terms
SVL
Between 1 and 8 inter-chassis links, for control-plane and data-plane traffic.
DAD
One worst case scenario, is the SVL fails, and both switches go Active/Active.
There are lot of bad effects from this:
- SVI IP Duplication
- SSH PKI Duplication
- STP Bridge ID Duplication
To help prevent this, it’s recommended to configure DAD links.
References
Products - Cisco Catalyst 9000 Platform StackWise Virtual White Paper - Cisco