The Xserve hung during shutdown and I had to do a hard reset, it booted up again but would not connect to the promise raid (were all the accounts are held).
Looked in System Profiler the fibre card was there and seeing the raid. Went to Disk Utility the drive was there but not mounted. Try to mount the drive and failed.
It recommended doing First Aid. So went to Verify Disk and got Error. This disk need to be repairs. Click Repair Disk.
So clicked Repair Disk, very quickly Volume repair complete came up quite quickly but now it is just sitting Updating boot support partitions for the volume as required.
Fingers crossed on this one.