Devices in a chassis cluster can be upgraded separately one at a time; some models allow one device after the other to be upgraded using failover and an in-service software upgrade (ISSU) to reduce the operational impact of the upgrade.
To upgrade each device in a chassis cluster separately:
During this type of chassis cluster upgrade, a service disruption of about 3 to 5 minutes occurs.
- Load the new image file on node 0.
- Perform the image upgrade without rebooting the node by entering:
request system software add image_name
- Load the new image file on node 1.
- Repeat Step 2.
- Reboot both nodes simultaneously.