[libvirt] Proposal: A place to store metadata about guests

[Richard W.M. Jones]

I think we need a place to store general metadata about guests.

Here are some uses:

 - Store data about available installer ISOs, guests which are
   archived and not known to libvirt.

 - Replace the guest inspection thread in virt-manager.  virt-manager
   would just collect the data from the store.  The inspection data
   would be generated by another process.

 - Expand on <description/> field in the libvirt XML, and satisfy
   various requests we've had for a place to store metadata and extend
   libvirt XML.

 - Store data on behalf of applications, esp. virt-manager.

I'm not envisaging a database or daemon for this.  Just a simple
directory per host containing flat files.  Perhaps we can add some
tools or a library to make creation/querying of these files easy.  It
would be nice if the database was made available over the network
(Avahi?).

You could also use this database to answer questions like:

 - "Do I have a Debian wheezy 32 bit guest anywhere on my network?"

 - "Does any guest have libpng <= <vulnerable-version> installed?"

 - "Bring up a Fedora 14 instance" (the tools would have to locate a
   suitable install ISO and put together the correct virt-install
   command line)

There is some crossover with VDSM and even RHEV-M here.

Thoughts?

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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