[libvirt] [PATCH] Expose SLIRP attributes

[Laine Stump]

On 03/28/2014 12:26 PM, Richard W.M. Jones wrote:
> On Fri, Mar 28, 2014 at 08:47:48AM +0000, Richard W.M. Jones wrote:
>> On Fri, Mar 28, 2014 at 10:33:39AM +0200, Laine Stump wrote:
>>> Beyond that, a question not with your patch, but with qemu's
>>> implemenation - does it always assume that the gateway address is
>>> $network.1 ?
>> Actually network.2.  The default addresses are:
>>
>>                            network: 10.0.2.0/24 (ie. mask 255.255.255.0)
>>                    default gateway: 10.0.2.2
>>                         dns server: 10.0.2.3
>>  dhcp start / normal guest address: 10.0.2.15
>>
>> It _is_ possible to change the gateway address, by specifying the
>> (confusingly named) 'host=' parameter.  As you suggested I think this
>> could be mapped to a gateway XML attribute, although libguestfs would
>> not need to use it.
> Another couple of thoughts on this patch.
>
> (1) Qemu rejects impossible network configurations -- for example, if
> you specify a default gateway address which is outside the network
> address range.  However it does so without giving any specific error
> messages, see:
>
> http://git.qemu.org/?p=qemu.git;a=blob;f=net/slirp.c;h=cce026bf12bbead8a2bc8b5d0a1af67877266dd9;hb=HEAD#l208
>
> Is there a case for making libvirt do the same checks and give proper
> error messages (and/or should we fix qemu)?

Yes, I agree we should check for things like that. (We should also check
for that in the <network> config, as someone once pointed out in a BZ; I
just keep forgetting to do it)