intrepid regression: MASTER NM 0.7 lacks bridge support

[Jonas Bonn]

Binary package hint: network-manager

Problem in network manager 0.7 in Intrepid:

I have the following configuration /etc/network/interfaces:

auto lo
iface lo inet loopback

auto br0
iface br0 inet dhcp
    bridge_ports eth0
    bridge_fd 5
    bridge_stp off
    bridge_maxwait 5

auto eth0
iface eth0 inet static
    address 0.0.0.0

Despite this configuration, network manager insists on getting an addres for eth0 via DHCP. I have to manually run:

ifconfig eth0 0.0.0.0

in order to get the network working. This configuration used to work in Hardy and earlier.

[Alexander Sack (asac)]

OK. Probably can be fixed by the "ifupdown" system config backend - though, NM probably needs to learn how to deal with just 0.0.0.0 address - if possible.

[Matteo Settenvini (tchernobog)]

This is increasingly important also if you use VirtualBox with host network configuration (almost all installations do that). It's quite painful to get this right w/ NM and VirtualBox. Here's my /etc/network/interfaces file:

auto lo
iface lo inet loopback

auto eth0
iface eth0 inet manual
        up ip link set $IFACE promisc on
        down ip link set $IFACE promisc off

auto tap0
iface tap0 inet manual
        up ip addr add 0.0.0.0 dev $IFACE
        down ip addr add 0.0.0.0 dev $IFACE
        tunctl_user matteo

auto br0
iface br0 inet manual
        up brctl stp $IFACE off
        up ip addr add 192.168.1.15/24 dev $IFACE
        up ip route add default via 192.168.1.1 dev $IFACE
        down ip route del default via 192.168.1.1 dev $IFACE
        down ip addr del 192.168.1.15/24 dev $IFACE
        down brctl stp $IFACE on
        bridge_ports all tap0

I'd consider this a bug rather than a wishlist: if a bridged interface exists and some ethernet cards are part of it, it's the bridge that should be used with DHCP/static address, not the ethernet cards.

Problem is, br0 and eth0 have the same MAC address, so you can't force NM to use one address instead of the other for configuration of the wired connection.

There should be another way to prioritize interfaces, or better always preferring bridges above ethernet cards when looking for a certain MAC address to set up the connection. This should be doable.

Sorry if I'm wrong. I'm just learning about bridging in GNU/Linux, so I may have made some wrong assumptions.

[ktp420 (ktp420)]

This is a regression and a bug so i can't be just wish list...right now there is no really good way to have bridged connections and network-manager.

[Sebastien Vajda (sebvajda)]

Indeed, I started playing with bridging and I had to disable NetworkManager as it kept on using DHCP to assign an address to eth0 even though it should only try that for br0.

This should be fixed urgently as bridging is something that one will come to pretty soon when starting playing with KVM / qemu.

[Divan (divan-santana)]

Is there anyway workable work around to make this work?
I also use KVM and bridge mode and want to use network-manager as kde4.1 is "network aware" also so I can use network manager for wireless.

But I want network-manager to be aware of my bridge mode and not say "offline".

[Dawid Pogorzelski (creative-mindworks)]

The workaround which i'm using at the moment for my wifi interface is the following:
-frist configure the interface from the network manager
-i'm using my eth1 in dhcp mode so as second step I removed everything from /etc/network/interfaces and left only this paramteter:

iface eth1 inet dhcp

note: auto eth1 should be removed too
now reboot the system,it should work fine

[Valentin Neacsu (valentin.neacsu)]

This should not be marked as a duplicate of #256054. The problem reported here refers to the lack of support for bridge interfaces by Network Manager. Steps to reproduce:
# ifconfig eth0 down
# brctl addbr br0
# brctl addif br0 eth0
# ifconfig (to confirm that the bridge is up and running)
At this point Network Manager reports no wired networks.