ADSM-L

Re: DISASTER Client Restores Slow

2002-05-17 11:08:04
Subject: Re: DISASTER Client Restores Slow
From: "Walker, Thomas" <Thomas.Walker AT EMICAP DOT COM>
Date: Fri, 17 May 2002 11:08:09 -0400
And using another backup solution won't result in many tape mounts as well?
TSM might be more mounts than others, but you only have to do one restore.
Remember, not using incremental forever means that you must resotre a
machine at least two times. How about using backup sets if time is that much
of an issue? If you have a couple hundred servers, I assume you have enough
tape drives to make this feasible? Using, say 5 drives, to restore 100
clients is probably a pipe dream. Also, do you run multiple servers? You can
easily pass the bus throughput of most machines when trying to restore this
much data. I guess what I'm saying is that people argue that tsm mounts a
lot of tapes and appears slow during DR restores, but in reality,  the
people that complain are usually trying to restore a lot of clients on a
severely under-sized configuration. I think matching your DR hardware setup
to your production setup is not a good idea. Most production setups are for
speed in backing up. This usually means they are not optimized for restore
speed. Also, prioritizing restores is key. I've cut DR times from originally
2 1/2 days of nightmare when I came here to about 17 hours with a fairly big
setup. In other words, don't just start all restores at once and let 100
clients fight for 6 drives. Of course it's gonna look slow!