Following up to myself here, I tracked the problem in my original posting down to a memory issue with the system board, found that I had to manually specify the amount of memory using the mem= parameter at boot time. Since then Asus has released an updated bios that has everything working fine without the parameter. Now there is a new issue that again appears to be related to the disks. When attempting to create a Xen guest I ran into problems with the guest OS filesystem (created on a logical volume) going read only. The volume group in question here is built on two 500 gig SATA disk set for 3Gbps combined into a RAID0 md. I traced this down through the dom0 var/log/messages file to the following error messages: Nov 7 18:22:43 xen0 kernel: raid0_make_request bug: can''t convert block across chunks or bigger than 256k 427819515 3 Nov 7 18:22:43 xen0 kernel: raid0_make_request bug: can''t convert block across chunks or bigger than 256k 427820029 4 Nov 7 18:22:43 xen0 kernel: raid0_make_request bug: can''t convert block across chunks or bigger than 256k 427820543 3 [deleted numerous duplicate messages] Nov 7 18:29:53 xen0 kernel: ata1: spurious interrupt (irq_stat 0x8 active_tag -84148995 sactive 0x37fd3fb) All of the rest of the guests are running on drbd block devices backed by matching logical volumes on this server and a peer, I created the same guest on a drbd device as the others are constructed and got three of the spurious interrupt messages but none of the raid0 messages. Does this look like a hardware issue or a configuration issue? My suspicion is that the buffering of going through drbd slowed the throughput enough to partially cover for a disk problem, Any thoughts on this would be welcomed. Regards, Chuck 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 _______________________________________________ Xen-users mailing list Xen-users@lists.xensource.com http://lists.xensource.com/xen-users