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
Update macOS
To fix this issue, update to macOS 10.14.4.
Mount your Xsan volume
If you previously unmounted your Xsan volume, you can mount it with the following command:
sudo xsanctl mount VolumeName --rw