I have been trying to get 12.04 bridging working with two 10GbE cards.

I have 2 10GbE cards in a linux box being used only for this bridge, 1 with 2 10GbaseT ports and another with a single CX4 port. I have 2 client computers connected with 10GbaseT cards and the CX4 card connects to a procurve switch.

I can get the bridging happening mostly the way that I want,

The clients receive dhcp information from the dhcp server (not the bridging machine) and can connect to and properly see the rest of the network. Speeds are ok, not amazing but working on that is another matter.

My problem is that the bridging machine has no internet access ... meaning I can't update anything or apt-get anything

It can ping all other machines on the local network. I've tried the helpful hints from: https://help.ubuntu.com/community/NetworkConnectionBridge "Enabling Internet Use on the Bridging Computer" and get the following

      RTNETLINK answers: File exists

but dhclient br0 does nothing for me :( I think if it is anything it a multiple route problem as both br0 and eth4 have ipaddresses ... even though I have only set it up so that br0 has one ...

Bridge setup details:

/etc/network/interface

      auto br0

      iface br0 inet static

      address 192.168.0.246

      netmask 255.255.255.0

      gateway 192.168.0.1

      broadcast 192.168.0.255

        dns-nameservers 192.168.0.1

        dns-search example.com

        dns-domain example.com

      #(eth2 & eth3 are the 10GbaseT)

      #(eth4 is the CX4 connection) 

        pre-up ip link set eth2 down

        pre-up ip link set eth3 down

        pre-up ip link set eth4 down

        pre-up brctl addbr br0

        pre-up brctl addif br0 eth4 eth3 eth2 

        pre-up ip addr flush dev eth3

        pre-up ip addr flush dev eth2

        pre-up ip addr flush dev eth4

        post-down ip link set eth4 down

        post-down ip link set eth2 down

        post-down ip link set eth3 down

        post-down ip link set br0 down

        post-down brctl delif br0 eth2 eth3 eth4

        post-down brctl delbr br0

ifconfig -a

      br0       Link encap:Ethernet  HWaddr 00:15:17:22:20:34  

      inet addr:192.168.0.102  Bcast:192.168.0.255  Mask:255.255.255.0

      inet6 addr: fe80::215:17ff:fe22:2034/64 Scope:Link

      UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

      RX packets:4957 errors:0 dropped:0 overruns:0 frame:0

      TX packets:1077 errors:0 dropped:0 overruns:0 carrier:0

      collisions:0 txqueuelen:0 

      RX bytes:596320 (596.3 KB)  TX bytes:139952 (139.9 KB)


      eth4      Link encap:Ethernet  HWaddr 00:60:dd:47:7c:05  

      inet addr:192.168.0.57  Bcast:192.168.0.255  Mask:255.255.255.0

      inet6 addr: fe80::260:ddff:fe47:7c05/64 Scope:Link

      UP BROADCAST RUNNING MULTICAST  MTU:9000  Metric:1

      RX packets:15391 errors:0 dropped:51 overruns:0 frame:0

      TX packets:1207 errors:0 dropped:0 overruns:0 carrier:0

      collisions:0 txqueuelen:1000 

      RX bytes:5916769 (5.9 MB)  TX bytes:154312 (154.3 KB)

      Interrupt:70 

route -n

      Kernel IP routing table

      Destination     Gateway         Genmask         Flags Metric Ref    Use Iface

      0.0.0.0         192.168.0.1     0.0.0.0         UG    0      0        0 eth4

      0.0.0.0         192.168.0.1     0.0.0.0         UG    100    0        0 br0

      169.254.0.0     0.0.0.0         255.255.0.0     U     1000   0        0 br0

      192.168.0.0     0.0.0.0         255.255.255.0   U     0      0        0 br0

      192.168.0.0     0.0.0.0         255.255.255.0   U     1      0        0 eth4