Revisit of U320 and U160 SCSI bus problems with FC3t2.91

[Thomas J. Baker]

On Sun, 2004-10-10 at 20:59 -0400, Bill Cronk wrote:
> I have consistantly had problems with booting systems which have a JBOD 
> RAID box and FC2 or FC3t2.91. The problem remains the same and the work 
> around I figured out is only temporary.
> 
> The servers are Tyan dual Athlon 2200+ to 2800+ MP motherboards. A 
> couple of models have the U160 and a couple have the U320 SCSI bus on 
> board. In all cases the installation boots fine without the RAID 
> configured. I found that I could boot the boxes then configure RAID0 or 
> RAID5 and all would work very well until I perform a reboot. Upon 
> rebooting then the boot cycle drops out into single user mode with 
> errors relating to the RAID configuration in the /etc/raidtab file. Mind 
> you the configuration works just fine since I already had it running 
> when I first set it up.
> 
> So when I set out to install FC3t2.91 I figured maybe the same issues 
> would not be present since there is now mdadm to use instead of the old 
> raidtools. Again I installed the FC3t2.91 (BTW, in all cases the FC 
> installs are all full installs), then set out to set up the RAID. So 
> when I figured out what was needed to properly configure the 
> /etc/mdadm.conf file and set the RAID5 configuration up that I wished to 
> use, I started the RAID up and it ran fine as expected. The RAID was 
> accesible, writable, and I even did an NFS export which could be 
> accessed by other computers. Then I rebooted and the same type of 
> failure occured dropping me out into single user mode stating that there 
> was a problem with the /dev/md0 configuration.
> 
> My work around:
> 
> So what I discovered I could do was simple, but not really a fix for the 
> problem. I found that if I removed the mount point in the /etc/fstab file:
> 
> /dev/md0  /export/db-f8017_raid5  reiserfs  defaults  0 0
> 
> and instead created a script file in /root which contained the following 
> 4 lines:
> 
> mdadm -A /dev/md0
> mdadm --details /dev/md0
> mount -t reiserfs /dev/md0 /export/db-f8017_raid5
> df
> 
> First line is close, but may be missing something since the files are on 
> my computers at work. Second line is just as a test reference point 
> showing that the RAID is active. Third line is my mount point while the 
> fourth shows the active mounts.
> 
> It accesses the same /etc/mdadm.conf file and the mount point is exactly 
> the way it originally was written in /etc/fstab. The system will boot 
> flawless and once logged in I can execute the script then the RAID comes 
> online and works perfectly.
> 
> So now I ask the questions... Why?? Any further info needed? Can someone 
> else setup a RAID box and recreate the problem to confirm that there are 
> issues in FC2 and FC3 with RAID durring the boot cycle? So far it 
> happens with a 144GB, 324GB, 657GB, and 2TB RAID boxes configured as 
> either RAID0 or RAID5, on internal U160 or U320 SCSI ports and an addon 
> U320 Adaptec card.
> 
> I think there is an issue with the events durring the boot cycle in that 
> it tries to mount the RAID before the RAID configuration sets the RAID up.
> 
> Bill
> 

Try changing the partition type on the raid disks to "linux raid
autodetect":

[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
-- 
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| Thomas Baker                                  email: tjb at unh.edu    |
| Systems Programmer                                                  |
| Research Computing Center                     voice: (603) 862-4490 |
| University of New Hampshire                     fax: (603) 862-1761 |
| 332 Morse Hall                                                      |
| Durham, NH 03824 USA              http://wintermute.sr.unh.edu/~tjb |
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