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Question on DR test using cluster backup to standalone system

 
Jan van den Ende
Honored Contributor

Re: Question on DR test using cluster backup to standalone system

Victor,

one more point of interest, which may or may not apply to your specific situation.

Let us assume that the environment is "quite big" (metrics decided by the environment specifics)

Let us further assume there are multiple applications running.

If you are preparing a DR site, I must assume that at least one of those apps is pretty critical.

Now for the site-specific homework:
Can you pick some application(s) to be most critical, some to be non-critical but rather sensitive to downtime, and/or some for which downtime is a nuisance, but acceptable for a somewhat longer time?

If you answer "yes" to that, then it is worth considering some more complex planning (and maybe adapt your backup procedure to accommodate the following).
(This is an extension to John G's words: "work backwards from your DR plan")

Consider first get ONLY your critical app(s) running.
At first, forget about the rest, and take the most painful heat off as quickly as possible. That IS what critical means!
Only then restore the "just important" stuff, and start that.
And then, re-evaluate the pro's and con's for the less sensitive stuff. If there is any reasonable chance to revert to "normal" conditions, it might perhaps not even be desirable to activate those on your DR!

And...

if you really are serious about DR, think twice about the other meaning of DR: Disaster Resiliance. Multi-site clusters REALLY DO offer benefits! They might just be worth the inverstment.

hth.

Proost.

Have one on me.

jpe
Don't rust yours pelled jacker to fine doll missed aches.
Robert Atkinson
Respected Contributor

Re: Question on DR test using cluster backup to standalone system

Victor,
we have a similar scenario for our DR plan, but I avoided switching off clustering altogether for this reason.

Certain software checks the SYSGEN cluster values and makes descisions based on them. Switching this off may have an effect on the software.

In my opinion, you're better off setting the expected votes down to 1 in SYSBOOT.

Robert.
Robert Atkinson
Respected Contributor

Re: Question on DR test using cluster backup to standalone system

Victor - any chance you can assign some points to those that have helped you?

Rob.