Planning deployment.
Determine the details
regarding how the installation of the patches will occur on production
systems. The frequency and timing of patch installation maintenance
windows must be chosen to meet with particular system down time limitations
and the need to install the new patches. You might choose the timing
of patching to coincide with your current maintenance windows. However,
for reactive patching, you may be required to use unscheduled maintenance.
For proactive patching, common intervals are quarterly, every other
quarter, and yearly. You should also consider the availability of
new patches and, if you are using standard HP-UX patch bundles, you
will likely want to choose a schedule that in some way coincides
with the release dates of new bundles.
Some specific criteria to consider when planning your change:
When are your maintenance windows? What length of
time are they?
In the event of patches causing negative side effects,
what steps will you take to back out changes, and how long will it
take to execute these steps?
To significantly reduce downtime, and to take advantage
of the ability to easily switch back to your original image if the
applied patches cause any negative side effects, consider using Dynamic
Root Disk (DRD). With DRD, you create a copy of the root disk (or
clone) that you can apply patches to, while your system is still up
and running. Once all the patches are loaded on the clone, you can
then reboot the system, using the clone as your active root volume.
If for any reason you decide that the patched root volume does not
perform as you desire, you can quickly reboot the original system
image. For more information, please see Chapter 10.
Printable version
