Does not discover routers after installing lxc

[Dylan McCall]

This is sort of the correct version of bug #969696, which I filed a while ago. upnp-router-control works perfectly — it discovers my DIR-655 router every time — out of the box. However, as soon as I install lxc, it stops working. It passes the UPnP Resource discovery stage but apparently never discovers a device.

Normal operation:
dylan@dylan-desktop ~ % upnp-router-control
* Initializing GUI...
* Showing GUI...
* Starting UPnP Resource discovery... done
==> Device Available: Xtreme N GIGABIT Router
Request for external IP address... successful [50.92.8.191]
Request for connection status info... successful
Connection info: Status: Connected, Uptime: 34027 sec.
Request for NAT and RSIP availability... successful [RSIP=no, NAT=yes]
* Destroying GUI...

After installing lxc:
dylan@dylan-desktop ~ % upnp-router-control
* Initializing GUI...
* Showing GUI...
* Starting UPnP Resource discovery... done
* Destroying GUI...

This looks like _specifically_ a conflict with lxc: after removing lxc (leaving its dependencies intact), upnp-router-control works happily again.

[Dylan McCall (dylanmccall)]

I thought this might be some configuration file mixing things up, but actually it's the lxc-net service. As long as lxc-net is running, this problem occurs. As soon as I run service lxc-net stop, upnp-router-control works happily.

I'll add lxc to this, because this effect doesn't appear to be documented :)

[Serge Hallyn (serge-hallyn)]

@Dylan,

thanks for reporting this bug. Before I dive deeper, do you already know why lxc-net is doing this? Is the other package installing a dnsmasq that binds to all interfaces?

[Dylan McCall (dylanmccall)]

Oh, hey, this _is_ a duplicate!

Looks like gupnp is meant to autodetect a network interface, and that is not working in this case. (It ends up using lxc's lxcbr0 interface). There is another bug report where the same problem occurs with Virtualbox's virbr0 interface, so I'll mark this as a duplicate of that.