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