D-Link DFL-1660 User Manual page 541

11.5. Upgrading an HA Cluster
Chapter 11. High Availability
Now, connect to the active unit (which is still running the old NetDefendOS version) with a CLI
console and issue the ha -deactivate command. This will cause the active unit to become inactive,
and the inactive to become active.
gw-world:/> ha -deactivate
HA Was: ACTIVE
HA going INACTIVE...
To check that the failover has completed successfully, an ha command can be issued again and the
text "INACTIVE" and "is ALIVE" should appear in the output.
D. Upgrade the newly inactive unit
When the failover is complete, upgrade the newly inactive unit with the new NetDefendOS version.
Just like step B, this is done in the normal way as though the unit were not part of a cluster.
E. Wait for resynchronization
Once the second software upgrade is complete, two units will automatically resynchronize and the
cluster will continue operation. The roles of active and inactive unit will have been reversed.
If it is desirable to make the active unit inactive, and the inactive unit active, the CLI command ha
-active can be used.
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