Automatic spice port selection

Automatic spice port selection

[Fabio Fantoni]

Time ago I have read somewhere that there is an option to automatically 
spice port in qemu as for vnc.
I started to write a libxl patch to add this feature like the vnc one:
https://github.com/Fantu/Xen/commit/63c54f354a34e7eb27b1c69016789a372a75843c

Testing this patch lead to a missing "to=" parameter and I didn't found 
nothing else.

Is there someone that can tell me that if it is possible to let qemu 
automatically assign a spice port like for vnc?

Thanks for any reply.

Re: Automatic spice port selection

[Fabio Fantoni]

Il 26/03/2014 17:15, Fabio Fantoni ha scritto:
> Time ago I have read somewhere that there is an option to 
> automatically spice port in qemu as for vnc.
> I started to write a libxl patch to add this feature like the vnc one:
> https://github.com/Fantu/Xen/commit/63c54f354a34e7eb27b1c69016789a372a75843c 
>
>
> Testing this patch lead to a missing "to=" parameter and I didn't 
> found nothing else.
>
> Is there someone that can tell me that if it is possible to let qemu 
> automatically assign a spice port like for vnc?
>
> Thanks for any reply.

Ping

Re: Automatic spice port selection

[Christophe Fergeau]

----- Mail original -----
> Il 26/03/2014 17:15, Fabio Fantoni ha scritto:
> > Time ago I have read somewhere that there is an option to
> > automatically spice port in qemu as for vnc.
> > I started to write a libxl patch to add this feature like the vnc one:
> > https://github.com/Fantu/Xen/commit/63c54f354a34e7eb27b1c69016789a372a75843c
> >
> >
> > Testing this patch lead to a missing "to=" parameter and I didn't
> > found nothing else.
> >
> > Is there someone that can tell me that if it is possible to let qemu
> > automatically assign a spice port like for vnc?

libvirt does automatic port assignemnt for SPICE, but I think it does it 'manually' (with no support from SPICE). I don't think spice-server/qemu has magic to automatically allocate the spice port to be used.

Christophe

Re: Automatic spice port selection

[Fabio Fantoni]

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2014-04-18 9:42 GMT+02:00 Christophe Fergeau <cfergeau@redhat.com>:

>
>
> ----- Mail original -----
> > Il 26/03/2014 17:15, Fabio Fantoni ha scritto:
> > > Time ago I have read somewhere that there is an option to
> > > automatically spice port in qemu as for vnc.
> > > I started to write a libxl patch to add this feature like the vnc one:
> > >
> https://github.com/Fantu/Xen/commit/63c54f354a34e7eb27b1c69016789a372a75843c
> > >
> > >
> > > Testing this patch lead to a missing "to=" parameter and I didn't
> > > found nothing else.
> > >
> > > Is there someone that can tell me that if it is possible to let qemu
> > > automatically assign a spice port like for vnc?
>
> libvirt does automatic port assignemnt for SPICE, but I think it does it
> 'manually' (with no support from SPICE). I don't think spice-server/qemu
> has magic to automatically allocate the spice port to be used.
>
> Christophe
>

Thanks for reply.
Can someone add spice automatic port selection on qemu similar to vnc ones
please?

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Re: [Qemu-devel] Automatic spice port selection

[Markus Armbruster]

Copying Gerd.

Fabio Fantoni <fabio.fantoni@m2r.biz> writes:

> 2014-04-18 9:42 GMT+02:00 Christophe Fergeau <cfergeau@redhat.com>:
>
>>
>>
>> ----- Mail original -----
>> > Il 26/03/2014 17:15, Fabio Fantoni ha scritto:
>> > > Time ago I have read somewhere that there is an option to
>> > > automatically spice port in qemu as for vnc.
>> > > I started to write a libxl patch to add this feature like the vnc one:
>> > >
>> https://github.com/Fantu/Xen/commit/63c54f354a34e7eb27b1c69016789a372a75843c
>> > >
>> > >
>> > > Testing this patch lead to a missing "to=" parameter and I didn't
>> > > found nothing else.
>> > >
>> > > Is there someone that can tell me that if it is possible to let qemu
>> > > automatically assign a spice port like for vnc?
>>
>> libvirt does automatic port assignemnt for SPICE, but I think it does it
>> 'manually' (with no support from SPICE). I don't think spice-server/qemu
>> has magic to automatically allocate the spice port to be used.
>>
>> Christophe
>>
>
> Thanks for reply.
> Can someone add spice automatic port selection on qemu similar to vnc ones
> please?

Re: [Qemu-devel] Automatic spice port selection

[Gerd Hoffmann]

  Hi,

> > Can someone add spice automatic port selection on qemu similar to vnc ones
> > please?

Not so easy as this is handled by spice-server not qemu, so this
requires some new interfaces to communicate the listening address to
qemu.  Otherwise you can't see the port selected in 'info spice', which
would make the whole thing pretty pointless.

Also note that the automatic port selection code in qemu is rarely used
in practice due to libvirt doing the port selection in typical setups.
And it is a bit flaky.  I've seen it happily grab port 5900 in ipv6
space even though it was in use in ipv4 space.  Which is probably not
the behavior expected by most users ...

cheers,
  Gerd

Re: [Qemu-devel] Automatic spice port selection

[Fabio Fantoni]

Il 22/04/2014 10:35, Gerd Hoffmann ha scritto:
>    Hi,
>
>>> Can someone add spice automatic port selection on qemu similar to vnc ones
>>> please?
> Not so easy as this is handled by spice-server not qemu, so this
> requires some new interfaces to communicate the listening address to
> qemu.  Otherwise you can't see the port selected in 'info spice', which
> would make the whole thing pretty pointless.
>
> Also note that the automatic port selection code in qemu is rarely used
> in practice due to libvirt doing the port selection in typical setups.
> And it is a bit flaky.  I've seen it happily grab port 5900 in ipv6
> space even though it was in use in ipv4 space.  Which is probably not
> the behavior expected by most users ...
>
> cheers,
>    Gerd

Thanks for your reply.
In xen I always used the vnc automatic port selection, which use the 
qemu's auto port selection.
Now I'm switching from vnc to spice on xen production systems, and I 
need an automatic port selection like vnc.
I believe that lot of xen users will like this feature and part of them 
still stuck on vnc due to the lack of it.
Could any one help to add this feature?
Why not implement it on libxl? (awaiting xen-devel feedback)

Thanks for any reply.