Which drives to pull on RAID5

[Deskey123]

Hi guys, I am the systems guy here at work. We have several sites that have servers with various apps. I patch these boxes on a monthly rotating cycle. For backup and disaster recovery purposes, I would like to pull the RAID'd drives in the event that patching breaks any of these boxes. In the event that it does, I can simply re-insert the hard drives that were pulled out. With that being said, RAID1 is obvious on which drives to pull out if their's only 2 drives (how would I figure out if there are 4+ drives in regards to which 2 to pull out?). Most of the servers are on RAID1+0 but we also have some in RAID5. If I want to pull drives off a RAID5 hard drive configuration for backup and disaster recovery purposes, which one(s) would I pull out? I know that the parity and info gets stored on one of the drives in the event that a hard drive in the RAID5 array goes down. Any assistance on this would be greatly appreciated.

 

[kjv1611]

I'm not real sure how to say this. I don't think knowing which drives to pull out is your problem. That is not a back-up solution. And if you don't know that, you need to get permission from your employer to seek out additional help, possibly a consultant or external IT firm with more expertise in dealing with backup and recovery. Or at the least, you need to get more training. If you just go in there pulling drives for "back-up", you're inevitably going to run into some MAJOR issues.

--

"If to err is human, then I must be some kind of human!" -Me

 

[goombawaho]

I totally agree. I don't really understand what you're trying to accomplish with "pulling drives" with RAID5. In theory, you can do that with a RAID1 setup - each drive being a mirror of the other and you would have a "before" copy of the system.

But in a RAID5 setup, there's nothing analogous. Please think about some type of imaging software that will capture your OS (minimal CYA) or entire hard drive data (OS + data) before you do any major updates/patches.

That is the only true way to have a backup of both the OS and the data. You should already be doing some sort of backup for the data (copying to another server, NAS, tape, etc.) at the very minimum.

Doing what you suggested is smart (being ready for an upgrade/patch gone bad on your OS) but it's not essential. But, the way you suggested is not even doable.