[CentOS] SATA disk issue

Chuck Mattern
Wed, 24 Oct 2007 11:33:12 -0000

I'm in the process of upgrading the hardware in a small cluster based on
CentOS 5 and Xen.  The old hardware had dual ide disks, the new dual
SATA.  In both cases /boot and / are on RAID 1 partitions on each of the
disks.  The remainder of the disk is a RAID 0 with volume group laid on
top.  Here's my problem, when booting to Xen the box gets to the point
of mounting filesystems for dom0, detects the logical volumes but cannot
find an ext3 filesystem on md1 then panics.  If booting straight to
Linux all goes fine.  The same configuration is running fine on the box
with the ide disks.  I'm wondering if the way Xen handles SATA (running
as SCSI devices (sda, sdb, etc.) might be part of this, seems unlikely
as the lv's in the vg are at least detected which would seem to be
comparable to being able to detect an ext3 filesystem.

FWIW I checked the grub.conf against the old config and there are no
pertinent differences and I compared the initrd's pointed to by each
stanza and they are identical (extracted to sepearate directories, did a
diff on the directories, compared the init scripts from the old initrd
and the new and found nothing not related to the additional hardware and
all seeming to be in order.  Other potentially significant differences:

AMD Athlon 4400 dual core CPU vs. Intel 2.4 GHz
4 gigs RAM vs. 2 gig RAM
ASUS M2A-VM system board vs. IBM NetVista

Any suggestions would be greatly appreciated.

Regards,
Chuck