I am trying to import an ovf appliance created for VMWare into our Xen infrastructure. The imported image uses hda rather than sda, and the appliance has some hard references that appear to be failing and/or creating problems. The appliance does a CentOS 5 kickstart, and I was able to modify that to work, but then the server itself installs with embedded references to sda that are in compiled code (found by using grep on the install files).

I'm new to Xen and have done a lot of searching that hints at the type of problem but can't figure out if it's possible to change, and how. These systems do not have an /etc/xen folder; some pages referenced editing the DomU config file and passing some kernel parameters, but I haven't been able to map that to what is running.

This is for XenServer 5.6.0, using local storage (LVM). Existing VMs use the xvd* devices, and if I mount the storage on another VM it shows up as xvdb, but the appliance VM sees it as hda.


Once you are "somewhat" able to boot your appliance on Xen, have you tried setting udev rules to rename hda to sda? Here is tutorial http://www.reactivated.net/writing_udev_rules.html on how to do that

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  • Thanks, that's helpful. I ended up just going through the appliance and figuring out the references; it wasn't as bad as it could have been (none of the actual application code references sda). I probably wouldn't do this just because of the level of maintenance required, but could be handy elsewhere. – Josh May 4 '13 at 1:33
  • It's not about manually renaming, and /dev/hda or /dev/sda will be referenced to /etc/fstab at most; and even there UUIDs or labels could be used. The naming difference means different controller type. /dev/xv* types means the disks are connected to a paravirtual controller, which is faster. /dev/hd* means disks connected to IDE/ATAPI emulated controller. Check you I/O, if you see delays try to switch controller. You'll also need to ensure that kernel modules are availble on the VM for the paravirtual devices. Centos 5 need a Xen kernel if I recall correctly. – Krackout Jun 28 at 9:03

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