Using 2 interfaces with network manager

[Uwe Geuder <networkmanagerList-ugeuder snkmail com>]

Hi!

I've never understood how network manager works if more than
1 network interface is in use. Is it designed for such usage at all?

What I want to do:

- use wlan0 to connect to the internet using network manager. Access
  points might change from time to time, e.g. when travelling.

- use eth0 for internet connection sharing (ICS). (using a cross connected
  Ethernet cable to provide an Internet connection to another device)
  I don't think network manager can do it, but I'm comfortable to do
  it manually (interface definition, IP forwarding and NAT)

So I configure eth0 in /etc/network/interfaces as

auto eth0
iface eth0 inet static
  address 192.168.77.1
  netmask ...
  ...

The other parts are not relevant for the discussion here.

Ideally I want to leave this definition there, whether I use the ICS
at the moment or not. (I don't think I have the need or even
possibility to connect to a wired network)


This works without problems in Kubuntu Lucid (nm 0.8.0) with 
knetworkmanager.

However, in Ubuntu Lucid and Xubuntu Lucid (same nm version), which
both use nm-applet instead of knetworkmanager there is a nasty
problem. It works as long a previously defined WLAN is in
range. But whenever no previously defined WLAN is in range,
nm-applet is completely invisible. The "not connected" icon is just
not there. And without having nm-applet visible I cannot really use
any network.

Well, I could scan for WLANs from the commandline, start
nm-connection-editor from the command line and define the network. But
then I have still to log out (or even reboot?) What i currently do is
to edit /etc/network/interfaces each time I want to connect to a new
WLAN.  I remove eth0 from there and reboot (at least I have not found
any way without rebooting. Just shutting eth0 down does not help.)
After having defined the new WLAN using nm-applet I can revert the
changes in /etc/network/interfaces.

Needless to say, that's not really pain free networking.

Is there any better solution? Is it a bug or feature that nm-applet
gets completely invisible?

Regards,

Uwe


P.S. Please bear with me that I have not yet tried nm 0.8.1. I just
didn't dare to possibly screw everything up by rpelacing Ubuntu's nm
with another version.