[libvirt] [PATCH] qemu: configurable VNC port boundaries for domains

[Daniel P. Berrange]

On Tue, May 22, 2012 at 11:00:16AM -0400, Dave Allan wrote:
> On Tue, May 22, 2012 at 04:10:03PM +0200, Martin Kletzander wrote:
> > The defines QEMU_VNC_PORT_MIN and QEMU_VNC_PORT_MAX were used to find
> > free port when starting domains. As this was hardcoded to the same
> > ports as default VNC servers, there were races with these other
> > programs. This patch includes the possibility to change the default
> > starting port as well as the maximum port in qemu config file.
> 
> Hi Martin,
> 
> Two design comments:
> 
> 1) https://bugzilla.redhat.com/show_bug.cgi?id=782814 requests that
> the default port be changed to avoid conflicts, which seems reasonable
> to me.

I disagree - for as long as KVM and Xen have existed, all guests have
had ports starting at 5900 & we should not be changing that. libvirt
should be checking for a clash before starting a guest, so there should
not be any functional problem here. Moving to another port range is
merely a nicety that we don't need todo by default, merely give admins
the ability.

> 
> 2) I agree with the config option since most applications on the
> system will want the system defaults.  However, IMO in this case an
> application writer should be given the option in the XML to override
> the system default.

I don't really think this is worth while either. I don't really think
that apps need / want the ability to override the system ranges here
on a per guest basis

Daniel
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