Primary/Backup Switch Redundancy

When your stack is operational, one switch is the primary switch, responsible for running network protocols and managing the stack.

To provide recovery in case of a break in the stack connections, you can configure redundancy by designating a backup switch to take over as primary if the primary switch fails. When you perform the initial software configuration of the stack, the “easy setup” configuration option automatically configures redundancy, with slot 1 as the primary and slot 2 as the backup. You can also configure additional switches as “primary-capable,” meaning they can become a stack primary in case the initial backup switch fails.

When assigning the primary and backup roles in mixed stacks, consider the feature scalability and the speed of each switch model. The easy setup configuration process selects primary and backup switches based on capability and speed. The following list shows the capabilities based on the ability to cross stack with other switch families. The most capable switches are shown at the top of each list:

1. 5520 Series
2. 5420 Series
3. 5320 Series

Important

5320 Series switches can be stacked with themselves, or with 5420 Series and 5520 Series using Alternate stacking. The 5320 Series can only act as a Standby node in a 5420 Series or 5520 Series Primary configuration. The 5320 Series cannot act as a Backup node when the Primary node is either a 5420 Series or 5520 Series.

Beginning with Switch Engine 31.6, 5320 Series switches can stack with 5520 Series switches by installing a 5520-VIM-4X VIM. The last two ports on the 5520-VIM-4X can be used as 10 GbE stack ports when Alternate stacking is selected. The two stack ports on the 5520-VIM-4X support both SFP+ direct attach and optical transceivers.

Note

Models 5320-24T-4X-XT and 5320-24T-24S-4XE-XT can only be stacked with themselves using Native V40 stacking.