Ignite-UX and MirrorDisk/UX

Abstract
It is a common misconception that Ignite-UX cannot be used with systems containing mirrored disks.
While it is true that Ignite-UX does not have any built-in support for mirrored disks, it is not true that
Ignite-UX cannot be used on systems with mirrored disks. Ignite-UX is still a very valuable tool for
use on systems configured with LVM mirroring.
This white paper has two primary goals:
1. Explain benefits and limitations of using Ignite-UX with LVM mirroring.
2. Explain how to use Ignite-UX with LVM mirroring
Introduction
Ignite-UX is a tool set used for the deployment (cold installation) and recovery of HP-UX on HP
systems. The make_tape_recovery and make_net_recovery tools are used to build a
customized recovery image that can be used in the event of a root volume group failure.
MirrorDisk/UX must be installed on a system to enable LVM mirroring functionality. None of the
Ignite-UX tools are "aware" of mirrored disks.
This white paper has not yet been updated to provide instructions on how to automatically re-mirror
a system after recovery with HP-UX 11i v3. It is expected that Ignite-UX configuration required will
be substantially different to what is already presented in this white paper. A new section will be
added to this white paper addressing re-mirroring HP-UX 11i v3 boot disks during the first half of
2008.
Deployment
In the case of cold installation (deployment), the fact that Ignite-UX is not aware of mirrored disks
means:
• When describing how your system's disks will be configured using the Ignite-UX user interface, it
is not possible to specify any disk mirroring information.
• There are no Ignite-UX configuration file keywords that allow you to specify any disk mirroring.
It is, of course, possible to use Ignite-UX to cold install your system. You can then set up your
system’s mirrored disks with the LVM commands, or by using System Administration Manager
(SAM) or System Management Homepage (SMH) (for all volume groups except the root volume
group).
System Recovery
In the case of recovery (make_tape_recovery and make_net_recovery), the fact that Ignite-
UX is not aware of mirrored disks means that the system being recovered may have had mirrored
disks prior to the problem that forced the system recovery. Of course, with a mirrored root disk you
are much less likely to ever need to recover a failed root disk using make_tape_recovery or
make_net_recovery. Nonetheless, mirroring your root disk does not cover all of the cases that
system recovery can handle. For example:
• There has been a catastrophic software error on the root disk that has also affected the mirror.
For example, executing rm -rf * while in the root (/) directory.
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