Re: What makes /dev/hdb1 say it's mounted/active when it isn't?
On 2 Mar 2004 at 17:47, CW Harris wrote:
> Shouldn't matter, as long as your BIOS can boot it (which it obviously
> can).
It can, but is there any possibility that's it's requiring the
controller or HD to be "active" as far as the kernel is concerned? I
can't see how that's the case but my grasp of the mbr and partitions
has always been shakey.
> > mdadm --create /dev/md0 --level=1 --raid-disks=2 missing /dev/hdc1
> ^ ^ ^ ^ ^ ^ ^
> Okay, I haven't used the mdadm (I used raidtools2), but shouldn't this
> be hdb1 missing?
I don't think so, it's straight out of that howto (I pretty sure). I
think it is reserving a first disc, unspecified, as failed, in a two
disc array in which the second disc is active and is /dev/hdc1
I've tried using /etc/raidtab setting up essentially the raid1 config
that's supplied but tweaking to /dev/hdb1 and /dev/hdc1 and ending
with a failed-disk line:
# Sample raid-1 configuration
raiddev /dev/md0
raid-level 1
nr-raid-disks 2
nr-spare-disks 0
chunk-size 4
device /dev/hdc1
raid-disk 0
device /dev/hdb1
raid-disk 1
failed-disk 1
and that has the same result (I think the /etc/raidtab is spurious
since, as I understand it, this is actually stored in the persistent
superblock??)
> > which worked fine, mkfs -t ext3 /dev/hdc1, mount it to /mnt1,
>
> and then shouldn't you have a working /dev/md0 to mkfs -t ext3
> /dev/md0?
Sorry, me being stupid in what I wrote, indeed so. I was getting a
working degraded array with one working drive and it was that I
formatted. Sorry.
> If above was incorrect, then hdb1 would be part of the (active) RAID?
> so you can't import it again.
cat /proc/mdstat doesn't show it as active:
cat /proc/mdstat
Personalities : [raid1]
read_ahead 1024 sectors
md0 : active raid1 hdc1[1]
78124928 blocks [2/1] [_U]
unused devices: <none>
I read that as sayng that it's a degraded array currently with just
the one drive in it, /dev/hdc1, and with space for a second.
> I haven't done that much RAID, and not with mdadm. But if my comments
> above are correct, maybe this is your problem?
Much thanks, and I'm happy to be corrected, but I think they're not
the problem though one of them was a typo of mine in the Email,
fdsk'ing the raw drive not the array, that several people have noted.
_ANY_ suggestions welcome: it feels so lame to just use that second
drive to mirror the first with a regular cp -aux / /mnt2 or something
like that, though I'm starting to think that's the time efficient
option given how much time setting up this server has cost me!
Cheers all,
C
PSYCTC: Psychotherapy, Psychology, Psychiatry, Counselling
and Therapeutic Communities; practice, research,
teaching and consultancy.
Chris Evans & Jo-anne Carlyle
http://psyctc.org/ Email: chris@psyctc.org
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