Best Practices for Integrity Virtual Machines

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Figure 6 – Data protection on the VM Host protects virtual mass storage and is
easier than repeating it on each VM
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Integrity VM Host
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MIRROR
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Integrity VM Host
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Using Multi-Path Technologies with Integrity VM
Logical volumes as virtual disks provide high availability since they have multi-path and mirroring
capability built in. You also get a choice between LVM (PVlinks) or VxVM (DMP) which allows further
flexibility.
However, the VM Host has only one multi-path option for disks – Secure Path. Note that Secure Path
has restrictions on which hardware devices it supports.
Files, being at the top of the IO stack, enjoy the ability to use any multi-path/mirroring/RAID option
available on HP-UX. Also, since they are easy to move, they can be backed up on another system
easily. However, if one doesn't set up HA for them using something underneath, then they have
nothing to protect them from being destroyed.
Partitions can use 2 multi-path options in 11.23 – EMC PowerPath and Secure Path – however, they
have to rely on the disk technologies for RAID functionality and they are not supported for use with off-
line migration of VMs.
Any redundancy strategy should be implemented on the VM Host – replication on the VM is not
supported. This applies to technologies such as SecurePath, PowerPath, and PVLinks. The primary
path to any storage unit should be the only path used by a VM as a virtual hard drive. That is,
secondary paths must not be used by VMs as virtual hard drives.
Managing Virtual Storage on the VM Host
Disks are arguably the easiest logical storage to manage on the VM Host because the mapping of the
virtual storage to physical storage is the simplest. This is a big advantage when one wants to make a
change in the data center and understand what system(s) are impacted. Disk use can be identified
with tools such as System Management Homepage (SMH) and hpvmdevmgmt. Disks are also the