Open Stack

Hello,

If I understood correctly, there are 3 ways to provide guest OS with some data 
(SSH keys, for example):

1. mount guest root fs on host (with libguestfs) and copy data there.
2. config drive and cloud-init
3. nova metadata service and cloud-init


All 3 methods do almost the same thing and can be enabled or disabled in nova 
config file. So which one is preferred? How do people usually configure their 
openstack clusters?

I'm asking, because we are going to extend nova/libvirt driver to support our 
virtualization solution (parallels driver in libvirt) and it seems it will not 
work as is and requires some development. Which method is first-priority and 
used by most people? 

-- 
Dmitry Guryanov