CoreOS XenServer Install Fix

I’ve been playing around with the new OS on the block CoreOS. After running it locally with Vagrant I wanted to get it up and running on our XenServer test pool.

I grabbed the ISO, created a new VM and installed it without issue. However after rebooting it just looped indefinity.

After a chat in the helpful IRC channel it turns out kexec was not being disabled for Xen installs, the fix below sorts this out post install. This has been addressed and should be in the alpha channel shortly but in the mean time hopefully someone finds this useful.

After the install you’ll need to tweak the boot partition as follows:

sudo -s
mount LABEL=EFI-SYSTEM /mnt
echo "DEFAULT coreos.A" > /mnt/syslinux/default.cfg
umount /mnt

This might disappear after an update in which case booting the install os and repeating the above should work, either way this should get you up and running.