On Tue, 21 Nov 2006, John Reeves wrote: > On Tue, 21 Nov 2006 21:13:00 +0100, "Henrik Holst" > <henrik.holst@xxxxxxxxxx> said: > > > Having a great deal of difficulty getting my 3 disk RAID 5 array to > > > reappear on restart, Ubuntu 6.10. > ... < snip > ... > > > the only way I can get > > > the RAID Array to assemble is to issue the following: > > > > > > mknod -m 0660 /dev/md0 b 9 0 > > > mdadm --assemble /dev/md0 /dev/sda1 /dev/sdb1 /dev/sdc1 > > > Try "dpkg-reconfigure mdadm" as root. Under Debian this will give you > > the chance to configure the startup configuration for all software raids > > in the system. Under any cirtumstances you should not have to use mknod. > > Instead try adding the --auto=yes switch to mdadm. Then mdadm will > > create the node itself. > > That's the one! Blowing away my current mdadm.conf and issuing a > dpkg-reconfigure mdadm bought my raid online with the subsequent reboot > - I am very greatful! Now I guess I would like to know where I go wrong > :) > > I created the raid in the first place by issuing a: > > # sudo mdadm --create --verbose /dev/md0 --level=5 --raid-devices=3 \ > /dev/sda1 /dev/sdb1 /dev/sdc1 > > After this, no mdadm.conf file was created for me, so I made by own by > issuing: > > # mdadm --detail --scan >> /etc/mdadm/mdadm.conf > > And thats when the whole "assemble" on boot problem came from. I > presume that the above command (--detail --scan) is not the correct way > to make the mdadm.conf file - how should it be made? that's fine, but you need a "DEVICE partitions" line as well... that's what i suspect your problem was. dpkg-reconfigure probably created it for you. you should look -- because if it put in a "DEVICE /dev/sda1 /dev/sdb1 /dev/sdc1" line then you really want to change it to "partitions"... so that it can handle device renames properly. > Finally, on a side note, I have formatted this array (/dev/md0) with > ext3, I planned to exapand the array in the future by adding extra disks > - I presume I can do this with 'mdadm --grow' (and some extra research! > :) Am I correct on this assumption? yep. -dean - 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
