fedora-test-list Digest, Vol 8, Issue 50

[ngc4013 at cox.net]

> Date: Mon, 11 Oct 2004 10:58:44 -0400
> From: "Thomas J. Baker" <tjb at unh.edu>
> 
> On Sun, 2004-10-10 at 20:59 -0400, Bill Cronk wrote:
--- Cut ---
> 
> [root at wintermute tjb]# fdisk -l /dev/sdc
> 
> Disk /dev/sdc: 18.3 GB, 18351959040 bytes
> 255 heads, 63 sectors/track, 2231 cylinders
> Units = cylinders of 16065 * 512 = 8225280 bytes
> 
>    Device Boot      Start         End      Blocks   Id  System
> /dev/sdc1   *           1        2231    17920476   fd  Linux raid
> autodetect
> [root at wintermute tjb]#
> 
> This allows them to be autodetected at boot time.
> 
> tjb
> -- 
> 

Thanks Tom, it seems to work now, but makes me wonder how it worked on the same type hardware setup with FC1 and SuSE. The drive flag 'Linux Raid Autodetect' is a new one on me. Can't imagine the last time I actually had to change a drive ID.

So this has now opened up another can of worms...

I have two LVSD SCSI ports on this card and two 2TB RAID boxes with 14 drives each. Boot order is correct, but the mount is reversed. I believe it has something to do with the point of creation for a RAID box. I think it gets an association with md0 or md1 and buries it in the superblocks. I can work around this part easily.

The next problem I have with this RAID setup is a simple one, but since I have never created a device file before it now has me stumped.

FC3T2 comes with only one RAID device file md0 or it was created when I created the RAID. The problem is that if it was created when I built the new RAID box then how do I create another device file such as /dev/md1 for the second box which has existing data on it?

I have tried doing:

zaboomafoo # mknod -m 660 /dev/md1 b 9 1

then zaboomafoo # chgrp disk /dev/md1

then zaboomafoo # ls -l /dev/md* 

which shows both md0 and md1 with identical permissions. Then I do mdadm -A /dev/md1 and the RAID starts up. I can mount it, check it, do an mdadm -D /dev/md1 and get the proper details, but after a reboot the /dev/md1 is gone away!!

Suggestions?

Bill Cronk