On Sun, Apr 4, 2010 at 12:34 PM, Mark Knecht <markknecht@xxxxxxxxx> wrote: > Hi, > I'm trying to do my first RAID install that puts / on RAID1 but I'm > having some trouble. Distro is Gentoo. I'm fairly certain the problem > is in my kernel because grub finds my RAID enabled kernel and starts > booting, but when it gets to the point where it is going to enable md0 > and mount / (or I think that's where it is) then it fails with a very > standard message: > > VFS - Unable to mount root fs on unknown-block(9,0) > > I know the machine works because I already have a non-RAID install > on sda. The new RAID install is on sdb & sdc and I'm booting to it > from sda. However so far I cannot get past the point where it figures > out what to do with /dev/md0 and moves on. > > I just wanted to check that the messages below, which occurred when > I first built the RAID, aren't a real killer. I am not storing /boot > on this device but I do want to store /. Is there any problem with > recent versions of grub doing this? I chose metadata=1.0 as mdadm > seemed happier with that choice, but I've been unable to mount this > RAID either. > > Again, if this is a kernel issue then I'll work it out. I've built > RAID0 and RAID1 support into the kernel, as well as other things, but > maybe I've missed something else. I just wanted to be doubly sure that > it's not a problem with grub as a boot loader. > > Thanks, > Mark > > keeper ~ # mdadm --create /dev/md0 --level=1 --raid-devices=2 > /dev/sdb3 /dev/sdc3 > mdadm: Note: this array has metadata at the start and > may not be suitable as a boot device. If you plan to > store '/' or '/boot' on this device please ensure that > your boot-loader understands md/v1.x metadata, or use > --metadata=1.0 > mdadm: Note: this array has metadata at the start and > may not be suitable as a boot device. If you plan to > store '/' or '/boot' on this device please ensure that > your boot-loader understands md/v1.x metadata, or use > --metadata=1.0 > Continue creating array? n > mdadm: create aborted. > keeper ~ # mdadm --create /dev/md0 --level=1 --raid-devices=2 > --metadata=1.0 /dev/sdb3 /dev/sdc3 > mdadm: array /dev/md0 started. > keeper ~ # cat /proc/mdstat > Personalities : [raid1] > md0 : active raid1 sdc3[1] sdb3[0] > 31463228 blocks super 1.0 [2/2] [UU] > [>....................] resync = 3.9% (1241664/31463228) > finish=5.2min speed=95512K/sec > > unused devices: <none> > keeper ~ # > Answering self - putting / on RAID1 only seems to work using --metadata=0.90. Tried it with higher versions and had no luck. Anyway, the system is running well now. Cheers, Mark -- 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
