Ensure that the cluster is healthy (Replica members are Operational, no errors in the logs, showing correct status on the 'Cluster Status' tab, etc).
If this is a version changing patch (eg 2.5.913->2.5.914), it is critical that the Release Notes for this new version are read and understood. For a version changing patch, the appliance must typically be placed into 'Maintenance Mode' prior to applying the patch. It is also recommended for version changing patches that the failover timeout be temporarily increased on the replicas to 3600 so they will not failover during the patch process.
Please review the documentation for the specific upgrade patch/Hotfix being installed so that any instructions specific to that Hotfix are understood and followed.
Once the Hotfix has been downloaded, it may be installed to the Primary. Please note the downloaded ZIP file does not get unzipped prior to applying the patch - the ZIP file is the patch file.
Installing the patch is done via the '/admin' interface under the 'Maint | Apply a Patch' menu. This may also be done via the https://ip_of_primary:8443/config GUI.
Select the file; then press 'Upload'.
Once the file has uploaded, enter any required 'Key' and 'Options'. Ensure that there are no leading or trailing spaces for either field as this will cause the patch to not apply. If the '/genkey' option is listed, it must be entered as '/genkey' not '\genkey' or '/ genkey' etc.
Ensure that any Target Replicas that should receive the patch are selected in the 'Target Replicas' field.
Press 'Apply Patch'.
The patch may be monitored via the 'Patch Log'. Note that version changing patches may cause the GUI to be inaccessible as they apply.
The Patch Log can be viewed for 'Single Day'; once the patch has applied successfully a line in the Patch Log should be seen similar to:
Patch successfully applied to system
Ensure that the correct timestamp is being reviewed.
Once the patch has been confirmed as successfully installed via the Patch Log on the Primary, it may also be confirmed via the 'System Status/Settings | Cluster Management | Member Status'. The installed patches will be listed under the Member Status (scroll down in the right-hand window to review the section 'Software Version & Hotfixes'). A line item regarding the recently installed patch should be shown with the Install Date / time.
To confirm this has been installed to the Replica; select the Replica in the 'Cluster Member' frame on the left, and select the 'Member Status' tab again to refresh for this Cluster Member. Scroll down to view installed Hotfixes.
Note that it may take a few minutes for the patch to copy and apply to the Replica.
It is also possible to review the Patch Log on the Replica via the https://ip_of_replica:8443/config GUI; and navigating to the "Maint | View Patch Log' tab; filtering for either 'Single Date' or 'All Dates'.
If the patch requires a reboot, this will be mentioned in the Description when downloading the patch. As mentioned above, if this is a version changing patch, the Release Notes must be read in full to determine any steps specific to the upgrade.