Hi,

You can always use REST-API to attach a cloud-init payload to the the machines you create - see the API example in:

http://www.ovirt.org/Features/Cloud-Init_Integration 

But the feature was somewhat broken in 3.5.5, recently fixed in 3.5.6: 

Please see that you should use the new <use_cloud_init>true</use_cloud_init> tag for 3.5.6

I have no experience with it in previous versions tough...

For the template sealing, I only set hostname to localhost, remove the infamous /etc/udev/rules.d/70-* files, delete HW lines form ifcfg-* files, unregister the machine from satellite etc. and poweroff. I do not use sys-unconfig (as it suggests), and did not need to run virt-sysprep - plain old sealing with deleting the necessary info seemed enough for me...

Regards,

--

Ekin.