Thank you all for the responses and help (you guys are FAST!)... I have successfully simulated a worst case scenario and 'rebuilt the arrays from scratch' while preserving all data. This is how I did it, for anyone who may run into the same jam: 1) removed OS hdd, temporarily installed scrap (read as: old 4 GB IDE HDD) hard drive. Installed same version of Linux - FC5, and same kernel. 2) copied (From cd backup) original mdadm.conf to /etc/mdadm.conf 3) as reccomended, executed following at command line... [abc@123]# /sbin/mdadm --assemble --uuid=[UUIDOFARRAY] --scan /dev/md1 4) rebooted This resulted in the array popping right up, and being accessible with all data in tact. Thank you again for all the help! I will now be working on a live cd to suite my taste, so that this all would be a little easier. FYI --- kernel being used is a prepackaged one from Livna Repository, 2.6.17-1.2187_FC5.stk16 #1 Mon Sep 25 17:32:45 EDT 2006 i686 mdadm version being used is, mdadm.i386 2.3.1-3 -Regards Vince --------------------------------------- Vince Spinelli University at Buffalo: EE --------------------------------------- "Kind of off his mental reservation." - ancient cowboy wisdom. --------------------------------------- Vince@xxxxxxxxxxxxxxxxxxxxx [vfs@xxxxxxxxxxx / vfs@xxxxxxxxxxxxxxx] > Assuming you can allow some downtime, get yourself a rescue CD such as > 'RIP' > > This will let you boot into the machine and run mdadm commands. > > You don't mention kernel/mdadm versions so you may want to check they're > close > on the rescue CD. > > Then try looking at the manpage around --assemble. > In particular you may want to try --scan and --uuid (if your RIP/live > kernel/mdadm support it) > > Also check out the examples... > > Assuming this is a sane machine and you're not in real disaster recovery > mode > with drives pulled in from random boxes then look at using the literal > string > "--config=partitions" (see the manpage) to avoid creating an mdadm.conf > with the > "DEVICE partitions" line - PITA on live CDs where you just want a command > line ;) > > If you can manage it, this will give you a nice warm feeling about > recovering > from a problem and it's pretty safe - just common sense like making sure > the > live CD kernel/mdadm are either up-to-date or match your production > system. > > HTH > > Also: >> I have thought about this, and I can't understand how 'mdadm' decides >> the >> health of an array. > > Each disk/partition used by md has a superblock which contains a unique > UUID and > other info, like the number of devices and the raid level. mdadm --scan > looks > into each partition for a superblock and notes this data. It can then > group all > the superblocks with the same UUID together and, for each group, knowing > how > many devices it should have, how many it has and how many it needs it can > decide > if the device can safely be assembled. > > David > PS Yes, I've done this (too many times!) > --------------------------------------------------------- SpinelliCreations Secure Webmail: Powered by SquirrelMail - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
