Add standby controllers to the Xsan SAN in macOS Server
You add additional standby metadata controllers to the SAN for data integrity, controller redundancy, and improved performance.
Each additional controller automatically gets its SAN configuration information from the first controller when it’s set up, and it also becomes an Open Directory Replica.
Connect a new computer to the SAN networks (Fibre Channel and Ethernet).
Set computer sleep to “Never” in the Energy Saver pane of System Preferences.
Launch Server app on the new computer, and go through initial Server setup.
Select Xsan from the list of advanced services.
Turn on the service.
The Xsan setup assistant appears.
Choose “Join an existing SAN as a controller,” then click Next.
Select the existing SAN from the list, then click Join.
If you don’t see the SAN, choose Other and enter the first controller’s IP address, administrator name, and password, then click Connect.
Enter an administrator name and password, then click Join.
Click Join to finish the assistant.
Verify the additional controller by selecting the Controllers tab, and inspecting the list.
In the list, you should see the primary controller, and the current computer.
Each controller has an Xsan configuration profile generated as part of adding it to the SAN. Similar to clients, removing the configuration profile from a controller removes it from the SAN. This operation can not be undone.