Thanks again Doug. With this direction, I have started looking into details of both formats and also to convert OVF -> libvirt domain XML format. Will post the review once I get a satisfactory code to share with the community. Appreciate your support/suggestion. Thanks! Ata
Date: Sun, 24 Jun 2012 17:27:03 -0500 Subject: Re: [libvirt] Intend to add OVA installation API From: cardoe@cardoe.com To: ata.husain@hotmail.com CC: libvir-list@redhat.com
On Sun, Jun 24, 2012 at 5:05 PM, Ata Bohra <ata.husain@hotmail.com> wrote:
Thanks Doug for your suggestions.
I believe you are correct about the relation between OVA and OVF. But I am not 100 % possitive about your suggestion: "defining an appropriate domain in libvirt". To understand better I am sharing more details about my plans:
1. Enhance libvirt interface code (libvirt.c) to provide a domain-independent routine: virDomainCreateOVA, an alternate API to create domain. To make client code real simple, this routine can take ova path as input and internally strip the OVA to extract required details. (planning to define a struct to hold all essential information). 2. Second, to enhance ESX driver to perform ESX specfic calls.
Given OVA is a tar file, the parsing is just another file open/read operation; it would be simple to perform it inside domain_conf.c (infact I have written a parser to strip information off OVA already).
Hope to get some comments/suggestions on above steps.
Thanks! Ata
Right. I'm suggesting you don't go that route and approach the problem from another angle. I did a little Googling since my last e-mail to at least make sure I understood the basics. So an OVF looks like the following:
virtualappliance/package.ovf virtualappliance/disk1.vmdk virtualappliance/disk2.vmdk virtualappliance/cdrom.iso virtualappliance/en-US-resources.xml
An OVA would simply be a tar of the above and named virtualappliance.ova package.ovf is an XML file containing the description of the hardware of the virtual machine, much like the XML that libvirt stores about domains. While en-US-resources.xml would be the US English descriptions of the machine and its hardware.
I'm suggesting you write an application that transforms package.ovf into libvirt's own domain XML format and simply call virDomainDefineXML() rather than adding API to libvirt itself. You could then further extend the application to allow you to take a libvirt domain and export it as a OVA.
Looking at VMWare and Xen, they both treat OVA/OVF as a foreign format and require a converter application to import them to their native internals so it wouldn't be much different than their approach.
Just my 2 cents. -- Doug Goldstein