On Wed, Feb 25, 2009 at 02:19:55AM -0500, Hal Vaughan wrote: > I have an embedded server, so using SATA and internal drives is not an > option. I've added 2 drives to this server and set up a RAID on it. > These drives came from another system, used as a backup RAID there (it's > got over 600 GB of data on it). I had hoped I could transfer them and > just tell mdadm to find the drives and assemble the RAID on this > computer, but there were several problems. > > When I started, the drives were /dev/sda and /dev/sdb. I had originally > set them up, on the other computer, by using the entire drives and not > partitioning them. This, and a few other issues, created problems, so I > finally had to just reformat the drives using one partition, then rsync > to transfer all that 600 GB of data BACK to this RAID (it took about 18 > hours to transfer that much data and restore it all!). > > I tried, when re-creating the RAID1, to specify the drives by UUID > numbers: > > mdadm --create --verbose /dev/md0 --level=1 --raid-devices=2 > UUID=f5c49ce9-826b-43d5-9642-0189701e251f > UUID=4c76d883-1b24-4195-bb67-a66e4503cab9 > > but it didn't work and I had to do this: > > mdadm --create --verbose /dev/md0 --level=1 --raid-devices=2 /dev/sda1 > /dev/sdb1 > > which worked fine. The RAID1 was created and I've got all the data back > on it. > > I tried to specify these drives in /etc/mdadm/mdadm.conf with the UUIDs > since I know the drives can change assignments between boots if they're > USB. I can't specify them in that file -- I get error messages when I > do. > > Now that the RAID1 is working, though, when I use vol_id to check the > drives, they both show the UUID of the RAID1 device and if I try "vol_id > --skip-raid /dev/sdb1", for example, both show the same UUID, the one > above from sda1 (starts with f5...). > > I rebooted, after all the work was done, and had some trouble with the > USB hub, but when it came up, the drives were /dev/sdb1 and /dev/sdc1 > and the RAID1 did not start at boot. It seems, with these drives on the > USB hub, that they may not be active when mdadm starts. > > As I see it, I have a couple problems: > > 1) How do I make mdadm delay until the USB drives are all online?
A really ugly way would be to add your own custom script to the initramfs. Find the right directory under /usr/share/initramfs-tools/scripts , and after you add your script rebuild the initramfs with update-initramfs -u Unless someone has a better suggestion. > 2) How do I specify the drives to mdadm, since they both now have the > same UUID and how would I do that anyway, since mdadm rejects "UUID=" in > the command line and config file? > > It's also quite possible that there's something else going on that I > don't see that could cause or solve problems, so if there's something > else I need to look at, I'm open to it. > > Thanks for any answers, helpful suggestions, and so on. > > > Hal > > > -- > To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.orgwith a > subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org > -- Tzafrir Cohen | tzaf...@jabber.org | VIM is http://tzafrir.org.il | | a Mutt's tzaf...@cohens.org.il | | best ICQ# 16849754 | | friend -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
