Kilian <[EMAIL PROTECTED]> writes: > In the last few days, I was struggling to convert a remote machine > with two identical SATA disks (sda and sdb) to a Software RAID > 1. Especially the boot-part was tricky as I had no console access to > the machine. The whole procedure was done remotely via SSH. I use the > md tools (mdadm) and lilo as bootloader. I chose LILO because IMHO > it's more straightforward in this setup than GRUB and I have no other > Operating Systems I would want to boot. > > The system was installed on the first disk, the second one has not > been used before. Those are the steps I went through: > > > 1. Install a Software-RAID capable kernel and boot the system with it; > Install the md tools: 'apt-get install mdadm';
Meaning any Debian kernel. :) > 2. partition the second harddrive (sdb). I created two partitions, a > large one at the beginning of the disk (sdb1) and a small > swap-partition at the end (sdb2). I do not use separate /boot > partitions. NOTE: disk speed differs by around a factor of 2 between start and end. Which one is the fast one can depend on the disk but usualy the start is. Better swap there. > NOTE: I do not use two swap spaces on the two disks; instead, I > create a RAID array consisting of the two smaller partitions on the > two discs and create the swap space on it. In case of a disk > failure, I don't need to reboot the system because the swap space > is also on RAID. Otherwise, a disk failure would toast one swap > space, probably leaving the system in a unusable state until > rebooted. It would cause processes to segfault all over and take down the system. > Important: both partitions need to be of the type 0xFD "Linux raid > autodetect" Actualy not. mdadm can work just as well without it. Doesn't hurt though. > 3. Create the RAID arrays: > > $ mdadm --create /dev/md0 --level=1 --raid-disks=2 missing /dev/sdb1 > $ mdadm --create /dev/md1 --level=1 --raid-disks=2 missing /dev/sdb2 > > > 4. Create filesystems > > $ mkfs -t xfs /dev/md0 > $ mkswap /dev/md1 > > I use XFS as filesystem because it has such nice features as online > resizing etc and is, IMHO, very stable and mature. Of course you can > use whatever you like. As does ext3, even more so. > 5. Copy the existing Debian system to the new RAID > > $ mkdir -p /mnt/newroot > $ mount /dev/md0 /mnt/newroot > $ cd / > $ find . -xdev | cpio -pm /mnt/newroot Fun, fun. A copy of /proc. That's a few Gig wasted depending on the size of /proc/kcore. MfG Goswin -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]