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Disk error, now md0 is gone - what was it? [SORTED]

Offline judgej

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Disk error, now md0 is gone - what was it? [SORTED]
« on: November 29, 2007, 11:31:24 AM »
I had a  corrupted filesystem overnight, and repaired the filesystems using fsck this morning. The server appears to boot up and work, and apart from some fragments of log files in lost+found, everything appears intact.

Except: when I look at /proc/mdstat, I only have two partitions:

Code: [Select]
md2 : active raid1 hdc2[0] hda2[1]
      312464128 blocks [2/2] [UU]

md1 : active raid1 hdc1[0] hda1[1]
      104320 blocks [2/2] [UU]

unused devices: <none>

So, where is /dev/md0, what was it when it was there, and how is my server still working without it? Is is swap space? Am I now automatically using a swap file on my main data partition or something?

And I'd better add: how can I get it back?

-- JJ

PS Tell me I'm not imagining things either. SME always had three partitions, and has three partitions on every other server I run, but this one just has the two now. I can't find any reference to '/dev/md0' in any of the log files, which is really confusing me.
« Last Edit: November 29, 2007, 06:18:51 PM by judgej »
-- Jason

Offline Stefano

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Re: Disk error, now md0 is gone - what was it?
« Reply #1 on: November 29, 2007, 11:41:36 AM »
sme 7.2

Code: [Select]
[root@fileserver ~]# cat /proc/mdstat
Personalities : [raid1]
md2 : active raid1 sdb2[0] sdc2[2] sda2[1]
      156183808 blocks [2/2] [UU]
     
md1 : active raid1 sdb1[0] sdc1[2] sda1[1]
      104320 blocks [2/2] [UU]
     
unused devices: <none>

as U can see, I have no md0.. and everything is working fine

HTH
Ciao
Stefano

Offline judgej

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Re: Disk error, now md0 is gone - what was it?
« Reply #2 on: November 29, 2007, 11:44:36 AM »
I guess the question changes to: why does every other SME server I run have three partitions? You may well be right, that this is fine, but I would like to understand the differences between this and similar SME servers.

Hold on - something has changed in the configuration. The raid shows sda, sdb and sdc - three disks for each partition. I only have TWO disks in the system. Am I reading that right?

Another update: just had a very nasty thought: I have an external HD plugged into a USB port. Could the raid have somehow commandeered that as a third disk? It would be nice if it is *able* to work like that, but this is my backup drive - I don't want it a part of my raid set. I would probably install a firewire drive if I wanted to do that. Nope - it's not doing that. Perhaps I have a controller fault mixing up two IDE channels. DOH! I was reading your disk setup, not mine. I thought you were just quoting me. I should learn to take notice of what I read. :oops:

-- JJ

PS As 'U' can see - lol ;-)
« Last Edit: November 29, 2007, 12:04:25 PM by judgej »
-- Jason

Offline psoren

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Re: Disk error, now md0 is gone - what was it?
« Reply #3 on: November 29, 2007, 05:16:19 PM »
I guess the question changes to: why does every other SME server I run have three partitions? You may well be right, that this is fine, but I would like to understand the differences between this and similar SME servers.

As far as i remember: If you upgrade from SME6 you have 3 partitions. If you install SME7 from scratch you don't.

Per

Offline judgej

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Re: Disk error, now md0 is gone - what was it?
« Reply #4 on: November 29, 2007, 06:14:18 PM »
Thanks - that would make sense. I can sleep easier tonight (obviously not too easy, because something messed up my disks last night, but a littler easier). I guess this was the kick up the jaxie I needed to get the hardware upgraded, because the motherboard is starting to play up.

-- JJ
-- Jason