[libvirt] [RFC] new preferences requirement

[Osier Yang]

Hi, all

   We have some new requirements of preferences, I listed
which of them I known, and think is useful as follows:

1) for the path of x509 certificate and keys of client

   The path of x509 certificate and keys of client is hard
coded in remote driver. e.g.

   /* Defaults for PKI directory. */
   # define LIBVIRT_PKI_DIR SYSCONFDIR "/pki"
   # define LIBVIRT_CACERT LIBVIRT_PKI_DIR "/CA/cacert.pem"
   # define LIBVIRT_CLIENTKEY LIBVIRT_PKI_DIR "/libvirt/private
/clientkey.pem"
   # define LIBVIRT_CLIENTCERT LIBVIRT_PKI_DIR "/libvirt/clientcert.pem"

2) for default default driver and subdriver for disk image

   Another requirement of new preference is default driver and subdriver
for disk images, currently we use "phy" for "driver" in virsh, and
"raw" for "subdriver" in qemu driver by default if user doesn't specify
them, it causes bugs, though we could say to user "you should use
options --driver and --subdriver", but these two options are optional.

   IMHO, the best solution for those bugs is to provide new preferences.

3) for default NIC and storage type

   "Chris Phillips" raised up the requirement not long ago:

   http://www.redhat.com/archives/libvirt-users/2010-November/msg00033.html

====================

   Should we add these new preferences(if they are really neccessary)
in qemu.conf? or create new config file, e.g. The approch Justin
raised up an approch before:
http://www.redhat.com/archives/libvir-list/2010-November/msg00651.html

   Though for Justin's approch, IMHO we'd better also to provide a
default config file, e.g. "/etc/libvirt/client.conf".

   Any feedback is welcomed, thanks

- Osier