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I've seen plenty of posts outlining the process of converting VMware Linux serves to RHEL Xen (not xenserver) but nothing much has helped me go the other way. I've tried a number of things including using mkinitrd (works great for LVM) but just can't get it right in this situation. Truth be told, I'm a newb at xm commands but I've gained a lot of ground.

Does anyone care to share the process they've followed to successfully complete this conversion? I have access to two environments currently:

  1. the original xm environment that has two Doms in it
  2. a successful vmware build after running vmware converter that I can boot in rescue mode (but not boot otherwise).

I realize also that XM images aren't bootable and need to overcome this (again I've tried but must be missing a detail).

I'd like to experiment with setting up xm for the conversion before running vmware converter since I feel like I've exhausted the process from the standpoint of linux rescue mode after successfully bringing all data over via vmware converter. (but I'll go either way if I can just get a couple of helpful hints...)

Patrick R
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  • Can you update your tag to specify which of VMWare's many products you're discussing please. – Chopper3 Mar 07 '11 at 20:37
  • @Chopper3 - I thought that the info in the title was good enough but now agree with you. I've updated the tags at your request. – Patrick R Mar 08 '11 at 12:32
  • Although having ESXi in the title helps us fix your problem we search on tags and the general 'vmware' one really isn't valid sorry, thanks for fixing. – Chopper3 Mar 08 '11 at 12:44

1 Answers1

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I have recently had to migrate a few centos 5.x VMs across to an ESXi cluster. A couple of things were needed before the VMs would boot.

  • Firstly you will need to ensure the rescue CD can see the hardisks: if you cant see them when you do a fdisk -l then try updating the SCSI controller type to LSI logic SAS.

  • Once you are able to see the disk in the rescue environment allow it to mount all the system partitions read/write when it asks. You will also need a network connection to download packages, so assign details when it asks.

  • If the automatic mounting fails you will need to manually mount the / partition and edit the /etc/fstab. The entres will be something like:

    /dev/xvda2 / ext4 defaults 1 1 change the xvda2 to sda2 or whatever it is in your case.

  • reboot to check that the disks are mounted by the rescue CD. Chroot into the /mnt/sysimage folder edit /etc/inittab you should delete an entry that looks like:

    co:2345:respawn:/sbin/agetty xvc0 9600 vt100-nav

    and ensure there is a correct entry such as:

    1:2345:respawn:/sbin/mingetty tty1 (sometimes this will need to be uncommented)

  • Now you can run a 'yum install kernel' and then create an initrd buy doing a:

    mkinitrd /boot/initrd-2.6.18-194.32.1.el5.img 2.6.18-194.32.1.el5

    replacing the 2.6.18-194.32.1.el5 with name of the kernel that you installed in the last step.

  • Now delete any xen related kernel entries in /etc/grub.conf leaving the newly added non-xen kernel and ensuring it is the default.

  • Exit the rescue environment and boot from hard-disk. With any luck the VM will boot as normal.

Its quite an long process and i might have missed something out, so id be interested in hearing how you get on.

Will
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  • looking forward to trying this. As I said, I've used mkinitrd but I did not attempt to install a kernel (kind of assumed I already had one - albeit a "broken" one. What VM environment did you migrate from? – Patrick R Mar 08 '11 at 12:28
  • fanastic! The two steps I had left out where the yum install kernel command and the comment out of co:2345... Thank you, thank you, thank you. Up-voted and accepted as answer. – Patrick R Mar 08 '11 at 13:43
  • Glad to hear this worked for you. I couldn't find this documented anywhere so it took quite a bit of figuring out! – Will Mar 08 '11 at 17:55