Managing Switch Stacks A switch stack can have up to eight stacking-capable switches connected through their StackWise ports. The stack members work together as a unified system. Layer 2 and Layer 3 protocols present the entire switch stack as a single entity to the network. Prerequisites for Switch Stacks, on page 1 Restrictions for Switch Stacks, on page 1 Information About Switch Stacks, on page 2 How to Configure a Switch Stack, on page 8 Configuration Examples for Switch Stacks, on page 10 Feature History for Switch Stacks, on page 23 Prerequisites for Switch Stacks • All the switches in the stack must be running the same license level as the active switch.
For information about license levels, see the System Management section of this guide. • All the switches in the switch stack must be running compatible software versions. Restrictions for Switch Stacks The following are restrictions for your switch stack configuration: • Only homogenous stacking is supported, that is, a stack of Cisco Catalyst 9300 Series Switches stack with only Cisco Catalyst 9300 Series Switches as stack members. Cisco Catalyst 9300L Series Switches stack with only Cisco Catalyst 9300L Series Switches as stack members. C9300-24UB, C9300-24UXB, and C9300-48UB switches can only be stacked with each other.
• During a switchover, when the standby device syncs with the active device, the following log message is displayed on the console: %SM-4-BADEVENT: Event 'standby_phy_link_up' is invalid for the current state 'NO_NEIGHBOR': rep_lsl_rx Gix/x/x -Traceback= Ignore this message. It does not have any functional or operational impact. Managing Switch Stacks 1