Successful System Recovery using Ignite-UX

Typically, the SLA is more important than the cost of implementing a recovery strategy because the
cost of implementing the SLA should be included in the total, agreed-upon cost (in capital and
recurring costs).
Testing recovery archives
It is critically important that recovery archives are tested when created, although it is not necessary
to test every recovery archive. If your business resumption plan relies on recovery archives in any
way, your plan cannot be considered completely tested until you test the recovery archives every
quarter or half-year, depending on how important it is that the archive is recoverable.
To ensure you understand the issues that impact the success of system recovery, HP recommends
you read the Successful System Cloning using Ignite-UX white paper prior to testing or creating any
recovery archive.
Archive recovery essentials
The following three topics are essential to understanding archive recovery:
•
Files that must not be restored from backup tapes
•
Recovering your applications
•
Operating system files to be recovered
Files that must not be restored from backup tapes
Operating systems files with the is_volatile SD-UX attribute set to false must never be
recovered from application backup tapes, as based on the attribute’s definition in sd(4):
is_volatile
Defines whether the file can be modified or removed.
If set to false, the file is not intended to be removed or modified by the administrator of the
system. The SD-UX product determines system configuration based upon when the recovery archive
was created. If files or directories are out of sync with the system configuration, certain SD-UX
patches may not install correctly, and it may not be possible to determine the cause of some
problems (especially if mixed and incompatible patches are recovered from backup tapes onto the
system).
You can use the swlist command with the option –a is_volatile to report the setting of
is_volatile, which is only kept at the file level, -l <file>.
Files for which is_volatile are set to true are intended to be modified by the system
administrator rather than by patching. These files can be safely restored from backup, for example
/etc/passwd. You must careful when recovering file systems and ensure that you do not
accidentally recover parts of HP-UX that should not be recovered from your backup tapes.
Recovering your applications
As part of your backup and recovery strategy, you should have already identified which files do or
do not need to be recovered to get the applications operational after a full system recovery. This is
extremely important when application files are placed into what are normally operating system
directories such as /usr/bin, /etc, or /usr/lib.
10