After you upgrade to macOS Mojave, your Xsan Metadata Controller (MDC) might unexpectedly restart due to a kernel panic with a message similar to this:
panic(cpu 6 caller 0xffffff7f911101b6): "CVFS ASSERTION FAILED: vnode_hasdirtyblks(vp) == 0 line 1220 file md_rwbuf.c”@/BuildRoot/Library/Caches/com.apple.xbs/Sources/XsanFS/XsanFS-613.200.4/snfs/client/vfs/nomad/md_debuglog.c:305
Apple is aware of the issue, and is investigating solutions.
Prevent the Xsan volume from mounting on MDCs
Here's what you can do until the issue is fixed in a future software update:
Add this line to your /etc/fstab file, and replace VolumeName with the name of your Xsan volume:
LABEL=VolumeName none acfs no
With this workaround in place on your Xsan MDC, Xsan client systems can continue to mount and use the Xsan volume normally. However, clients can't search the Xsan volume with Spotlight.