Re: [Qemu-devel] RFC: Qemu Guest Tools ISO

[Michael Roth <mdroth@linux.vnet.ibm.com>]

On 06/23/2011 06:38 AM, Daniel P. Berrange wrote:
> On Thu, Jun 23, 2011 at 12:08:26PM +0100, Stefan Hajnoczi wrote:
>> On Thu, Jun 23, 2011 at 10:29 AM, Alon Levy<alevy@redhat.com>  wrote:
>>> On Wed, Jun 22, 2011 at 01:55:25PM -0500, Michael Roth wrote:
>>>> Goal:
>>>>
>>>> Provide a mechanism, similar to vmware and virtualbox guest tools
>>>> ISOs, that allows us to easily distribute guest tools (and
>>>> potentially drivers) for linux and windows guests.
>>>
>>> What would be the advantage for linux guests, with their package managers already
>>> handling this task? I see how it would make testing easier with various linux
>>> distributions, but for management I wonder if it won't be easier to use the
>>> package management system to update the guests same as the hosts.
>>
>> If the guest tools come from the host QEMU we don't need complicated
>> compatibility testing and fallbacks.  Guest and host will be in sync
>> and support the same features.
>>
>> I'm not sure how we can update guest tools when the QEMU on the host
>> is updated though.
>
> While an ISO is a good option for the initial deployment, since it can
> be used to provide both the virtio drivers + agents together, once you
> have the virtio stuff installed in the guest, it might be worth exposing
> updated tools via a 9p filesystem mount. For Linux guest the 9p fs
> exposed could include a YUM repo (or equiv) which the guest update tool
> would automatically see and pull updates from, since 9pfs is "live"
> unlike an ISO.
>
> Regards,
> Daniel

Definitely, or at least some form of automating the install beyond the 
initial one. One approach would be extending the guest RPC agent that 
would ship with the ISO to be able to kick off a future update. 
Implementing in would be pretty simple too:

Guest agent: add RPC will execute the ISO installer
QMP: add command that will mount latest ISO as a cdrom then initiate the 
update via the guest agent RPC.

We could even take the ISO out of the equation after the initial 
install, since files can be pushed to the guest via guest 
agent/virtio-serial