Thanks for the answer. I did find the commands on this link later. Our upgrade went sucessfully.
Regarding "It is necessary to modify failover back on". I was told by support when they were onsite setting up our device to have the option turned off just so that when a controller goes bad, you don't want it to attempt to go back online. Anyways, how would I see what the configuration is set?
When we attempted using the cli to get info regarding the open cifs sessions, the command below doesn't work. It doesn't know what the session ID is ( after issuing vserver cifs session show -continuously-available !Yes -instance). We later used a combination of MMC (Microsoft console).
vserver cifs session file show -session-id session_ID
Anyways, we decided to shutdown the CIFS services to end all sessions but restarted back on right after the upgrade. Would it be fine if we had left the CIFS service at a stopped state and perform the upgrade?