You should be able to move disks between HP Proliant servers without any problems by following this guide (note: applies to single or mirrored disks only RAID 0+1).
This operation is useful when a server has died (just pull the disks and follow instructions for new server below) or a server is no longer connected to a storage expander where disks are allocated to it. In both cases you can then pull the data off the drive onto a production disk array.
If the server is still operating, logon to the server you are moving the disk from and start the HP Disk Array Configuration Utility – usually under Start, Programs, HP System Tools
Find the correct logical disk/partition that you are moving – select logical disk and choose more information (this should tell you which server is connected to which drives on a storage expander – look for host controller connecting and you should see the server name in brackets).
You can also select the physical view to guide you as to which bays disks are located.
Once you have identified the physical drive(s) unslot the drive (just single drive if part of raid array) from its bay and slot it into a spare bay on the new server or storage expander.
Open the HP Disk Array Configuration utility on the new server – you should see the new drive listed as unallocated.
Select create partition on new server and tick the new drive listed – keep defaults.
Select create logical drive for partition just created.
Select save changes.
Drive should now have mounted and been assigned a drive letter – try browsing to the drive on the new server.
Exit the array configuration utility on new server.
On old server delete the partition for the drive you just pulled out, save changes and exit the ACU.
Your done – you can now pull data off and restore to a production array etc.