A long time ago I posted on suggestions for setting up a software RAID. After months of planning I finally have things working after a late night last night - I just wanted to share my experience with the list so maybe someone can avoid the pitfalls I had: 1.) For Debian based (and probably any actually) systems - this documentation is the best you are going to get on how to do a remote RAID setup from an existing system, without data loss. I was able to do everything via SSH which was great: http://alioth.debian.org/projects/rootraiddoc 2.) If you use a seperate partition for /tmp - watch out what permissions you give it when creating a mount point (/mnt/tmp). 3.) With multiple partitions, be very careful how you use "cp -aux". e.g. "cp -aux /boot /mnt/boot" is bad - "cp -aux /boot/* /mnt/boot" is good. 4.) If you put swap on RAID, make sure you run mkswap on the raid partition and use swapon to initialize it. 5.) My biggest blunder - when you are copying data to your first RAID disk, shut down services like MySQL. I didn't do this and after copying data and syncing disks I had corrupt InnoDB tables because MySQL (and most db's) don't like it when you make disk copies of data files while the server is running. Thankfully there were nightly mysql backups to start a restore from. Thanks for the help from earlier posts, I can sleep a little better at night now. :) Josh -------- Original Message -------- Subject: [tclug-list] RAID questions Date: Tue, 20 Dec 2005 17:17:53 -0600 From: Josh Trutwin <josh at trutwins.homeip.net> To: tclug-list at mn-linux.org A while back one of the servers I help out with that a buddy of mine owns had a catastrophic hard drive failure. It wasn't a HUGE deal because we were slowly migrating off to a new server, but there still was some data loss. The newer server we're migrating to which I am more active in managing does not currently have redundant drives. I do a lot of off-site backup of important data, but I'm still very nervous about this situation and trying to push the owner to spend some money on more hardware. There isn't a hardware RAID controller so I am suggesting to the owner of the server to purchase a couple more disks so I can setup a software RAID solution as I've been reading up on here: http://www.tldp.org/HOWTO/Software-RAID-HOWTO.html Questions: 1.) Does anyone have experiences they can share with setting up a s/w RAID on an existing system? (Server is a Dell PowerEdge 1750 running Debian sid with 2.4.32 - I build the kernel myself - it is currently co-located which might make remote setup interesting) 2.) We can have a maximum of 3 drives on the SCSI controller. I am pushing to get two more drives matching the current drive. I was going to use one as a scratch space / archive area and then use the other to setup a software RAID. Sound ok or something better? 3.) RAID-1 seems to be the right solution for this kind of setup (only 2 disks, exact same size) Any other suggestions / war stories are most welcome. Thanks, Josh _______________________________________________ TCLUG Mailing List - Minneapolis/St. Paul, Minnesota tclug-list at mn-linux.org http://mailman.mn-linux.org/mailman/listinfo/tclug-list