Popping Mirrored Drives Out

[jim goodman]

Quick question.

We have a patching situation where the servers and apps are critical. We want to be able to back out by pulling one of the OS/APP mirrired drives. Adding a spare letting it rebuild. After the spare rebuild and reboot 1 of 3 came up with no prob and that other 2 exhibited the drive F1, F2 prompts for recovery.

What are the considerations or ramifications of pulling a live drive and doing what was done above?

Thanks,
Jim

[Vijay_44]

What was the 17xx error on post? IF you added a new drive offline, after the â failureâ that you simulated, you will get a prompt on POST stating a logical drive ( using the surviving member of the mirror) needs recovery and the F1 F2 option and one or them says F2 to rebuild (I think its F2).

[Paul_594]

If you are going to use this method I would make sure that you don't put the mirrored drive back in until the system is up and tested. At this stage simply hot plug the drive back in, I would not recommend re-inserting the drive while the system is powered off.

Doing it this way ensures that you have a working system and that the mirror rebuilds correctly.

P.S Hope you also have a good backup before doing the patching

[Richard Manson_1]

Jim,

* You are pulling a "live drive". That is, you pull the disk without shutting down the OS. That's right ?

What to you intend to do with it in case of failure of your patching process ?

My concern is the following : if you pull a disk from an active system, you can not expect that every current disk operations has been completed.
That is : some files might be inconsistent. For the registry or a database, that means corrupt.

In the situation I describe, the disk "pulled-out" is unusable.

* For the "F1-F2" prompt : I have seen a situation similar.
Two disks (one system, one application) had been pulled-out "live" (which is a mistake IMHO).

We tryed to reboot on the pair pulled-out. That is having removed the "good" ones after the shutdown, but no mirror reconstruction. Only the "pulled out" pair in place at their orignal place.

The reboot lead to the (expected) message. Trying to use the "F2 - interim mode" lead nowhere : the server tryed to boot from the stream on another SCSI card and then on the floppy !

(Later, on another server of the exact same model, we were able to start on those disk. Except that Windows never finished booting. I guess the registry has been wrecked by the "pull out live".)

Anyway, I can't understand why the pulled disk were not usable by the RAID controller on the boot attempts.

--Richard.

[jim goodman]

Thanks for the replies. The idea was to patch the OS on one drive and have the mirrored drive sitting aside in case of blow-up.

I haven't worked in hardware for a long time and I have seen it done before, but I have always had concerns about pulling a live drive from a running system.

I think I talked the customer into a better method of doing things.

- Jim