There are a number of Xsan troubleshooting scenarios that seem to call for uninstalling and reinstalling the Xsan software to resolve client configuration issues. If you are looking at a configuration issue, such as a single client not mounting a volume then you don’t actually have to uninstall the software, reinstall the software, run Software Update and then reboot and attempt to readd the client to Xsan Admin on the MDC and then attempt to mount. That’s a lot of crap when one step will reset a client back to how it was before it ever joined its first Xsan. Just delete the contents of the /Library/Filesystems/Xsan/config folder (but not the folder itself) and then reboot. On reboot the Xsan process is waiting to be controlled, so use Xsan Admin to add the client, it should be allocated the same serial number it had before and automatically mount the SAN volume(s). This will fix a few different client-specific issues. Having said this, don’t do it on a Metadata Controller unless you know what you’re doing!