Best Practices for Integrity Virtual Machines

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General Flexibility
When considering which type of storage to use – file, logical volume, disk, or partition – on the VM
Host, flexibility is an issue that may be of great importance in your VM configuration.
Logical volumes, created with VxVM or HP’s LVM, are easy to extend, import, or export. Each of
these actions may be applied on the VM Host to logical volumes serving as virtual disks – provided
the VM using those logical volumes has been shut down and powered off.
Virtual disks in the form of files on the VM Host are the easiest to transport. They may be moved from
one VM Host system to another in the same way any other file may be moved, for example, using ftp
or rcp. This flexibility makes files an ideal candidate for use as virtual DVDs.
Moving physical disks is possible, but not convenient. Hence, the use of entire disks local to the VM
Host limits flexibility. On the other hand, using LUNs associated with a SAN is arguably the most
flexible option. If an entire LUN on a SAN is used by a VM, then it may be used by a VM on another
VM Host provided that host has connectivity to that SAN storage. In fact, this means of storage is
recommended for any VM that may be migrated (using hpvmmigrate for example) from one VM
Host to another.
Finally, partitions offer the least flexibility in that they may not be modified in any way without losing
data.