
During the rollback, ports and services on the master chassis will be working normally, and the ports on the standby chassis will remain Down. The rollback process lasts at most 1 hour. In service port clustering mode, if the quick upgrade fails, the standby chassis will roll back to the old version and start, enter the single-chassis CSS state, restart and then join the CSS after the boards on the standby chassis register. In CSS card clustering mode, if the quick upgrade fails, the standby chassis will roll back to the old version and join the master chassis to set up a CSS. To view information about preceding quick upgrade failures, check the log CSSM/6/FASTUPGRADEROLLBACK.

Configurations cannot be restored or backed up in a batch for a long period during the upgrade of the standby chassis.


During a quick upgrade, if one of the following situations occurs, the upgrade will fail and then the system automatically finishes version and patch rollback:
