[libvir] How to seek a running QEMU instance

[Richard W.M. Jones]

On Tue, Mar 18, 2008 at 05:47:38PM +0300, Anton Protopopov wrote:
> I have the following question. How can virsh (or, more accurately, libvirt)
> detect a running QEMU vm, when latter was already started? For example, I
> have got the following:

As Dan says, it doesn't, but this is kind of a bug in libvirt.

It is in theory possible for libvirt to enumerate running qemu/kvm
instances, eg. by looking at the process table.  But this is rather
nasty.

A better way would be to allow qemu processes to drop a monitor socket
into a well-known directory; something like:

  qemu -monitor unix:/var/run/libvirt/monitors/<uuid>

(and perhaps wrap this up in a shell script to make it simpler for
users to start their own qemu instances and have them transparently
managed by libvirt).

This would also allow libvirtd to be restarted without killing the
qemu guests (I think ...).

Rich.

-- 
Richard Jones, Emerging Technologies, Red Hat  http://et.redhat.com/~rjones
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