Description of problem: The xenU can't find the specified root device. Xen0 is a xen kernel with PAE suppport (i don't know if it matters). Version-Release number of selected component (if applicable): kernel-xen-2.6.17-1.2174_FC5 How reproducible: static Steps to Reproduce: 1. boot the xen0 domain 2. xm create xenU Actual results: The xenU boots and fails on this error: VFS: Cannot open root device "hda1" or unknown-block(0,0) Please append a correct "root=" boot option Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) The relevant options in the configuration file are: disk = [ 'file:/DEVEL/Masters/2006/hd.img,hda1,w' ] root = "/dev/hda1 ro" this looks fine to me. Expected results: The disk image file specified in the xenU configuration should be detected and mounted correctly Additional info: The server running the xen0 domain is an ibm x365 booting with the noapic boot parameter (cf bug #204474). As soon as the xenU has crashed, i can't start anymore any xenU. The error message is: Error: Device 769 (vbd) could not be connected. Backend device not found. The only solution I found is a reboot. It's a bit annoying because x365 take a very long time to boot (at least 8min)... I will try with a xen0 kernel without PAE
Created attachment 135136 [details] Boot log of the xenU
Created attachment 135138 [details] xenU configuration file based on the xmexample1 included in the kernel-xen package
Adding ramdisk in domU config should work (works for me).
adding ramdisk in the domU config is worse, i can't even see the boot process, it instantly failed on this error: Using config file "/etc/xen/domU_pae". Error: Device 769 (vbd) could not be connected. Backend device not found. What is the device 769? seems to be something linked with disk access. It can't read the ramdisk or if i comment the ramdisk definition in the config file, it can't read the disk image of the root device. thank you anyway, i appreciate your help btw i found this bug #201764 to be quite similar with my problem (even if this one concerns x86_64), i will try to make an initrd with xenblk preloaded as they said
Created attachment 135270 [details] DomU boot log
domU with xenblk preloaded in the initrd still failed to boot but with a different error message it can't find a /dev/root... (cf Attachment #135270 [details])
it works perfectly on a xen0 kernel without PAE support so there is a problem with the kernel-xen supporting PAE
and now, it works with a vanilla kernel built from xen source 3.0.2-2, same machine, same config domU boots perfectly, so there is a real problem with kernel-2.6.17-1_2174xen package
same problem on Fedora Core 6 kernel-xen package
but works with an initrd preloading xenblk: mkinitrd --omit-scsi-modules --preload=xenblk /boot/myinitrd.img `uname -r` maybe domU try to access the real disk devices instead of the xen block devices provided by the dom0. FYI this server has scsi disks with an adaptec ServeRaid
To get the initrd loading xenblk automatically, it should have alias scsi_hostadapter xenblk in /etc/modprobe.conf. This should be set up automatically on all installs; it's only manually installing a PAE kernel-xen onto an existing non-PAE, fc5-or-earlier kernel-xenU that will need the manual config step.
*** Bug 216887 has been marked as a duplicate of this bug. ***