on 12-2-2008 10:31 AM Kai Schaetzl spake the following: > Scott Silva wrote on Sat, 29 Nov 2008 14:52:18 -0800: > >> Before you do anything, can you access the LVM's on /dev/sdb2? >> If so, make sure you back everything up as you will probably need to start >> over on the raid arrays. Worse case you will need a third drive for temporary >> storage. Best case, you can create new arrays on /dev/sda with only one >> member, migrate the data from sdb to sda, and then add sdb to the arrays. > > Thanks, I overlooked this message some days ago. I didn't need to back anything > up. I created the new RAID structure on disk 1 with missing mirrors and kept > the old structure on disk 2 that was now merely acting like normal > partitions/LVM. The hard part then was getting it to boot from the RAID. I > didn't know that the root device path is hardcoded in initrd and an error > message of "cannot switch to root" is not very helpful (now, a helpful error > message would have been just slightly different: "cannot switch to root path > /dev/md1"). I found that out when I finally unpacked the initrd. Once I knew > that getting it to boot was easy. > Then I moved all data to the new LVM/RAID partition on disk 1 and finally > copied the partition table to disk 2 and added the missing mirrors to the md > devices. It took actually a bit more copying to and fro as I experimented a bit > here and there (like what happens if you dd over a complete PV to an existing > md device or vice versa or if you can keep the data if you create an md device > on a partition that already holds data), but I was able to keep all the data > and system during this. > > Kai > As long as your system is back up, then no worries! -- MailScanner is like deodorant... You hope everybody uses it, and you notice quickly if they don't!!!! -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 250 bytes Desc: OpenPGP digital signature URL: <http://lists.centos.org/pipermail/centos/attachments/20081202/08f4892f/attachment-0004.sig>