Configuring HAU Groups

The HAU group feature determines which chassis, slot, or slots will be simultaneously upgraded. All chassis or system slots within the same HAU group are simultaneously upgraded. Each system slot belongs to an HAU group. HAU occurs one HAU group at a time. By default, there is one slot per group. Therefore, the default HAU behavior is to upgrade each system slot one at a time.

Because, in the case of the S-Series, HAU groups are upgraded one at a time, the total upgrade time increases with the number of HAU groups configured. In a large chassis it could take a significant amount of time to complete the upgrade and have all physical links back in operation. Upgrade time can be reduced by assigning multiple slots to the same HAU group. When planning system connections on the S-Series device, the overall upgrade time will be reduced to the degree that multiple slots can be configured into a single group and still retain sufficient resources in non-upgrading HAU groups to assure system operation.

All essential system capabilities on the device should be configured across multiple groups. For example, all LAGs configured on the device should provide sufficient redundancy between HAU groups for packets to continue forwarding on the LAG using chassis or slots belonging to HAU groups that are not upgrading.

Use the set boot high-availability group command in any command mode to configure an HAU group, specifying the group ID and the system slots that will be members of the HAU group.