Comments on: Linux bridge: MAC addresses and dynamic ports

By: Oseias Ferreira

Oseias Ferreira — Thu, 16 May 2013 18:26:59 +0000

Or you can use:

auto br1
iface br1 inet static
...
bridge_hw 00:22:aa:44:bb:cc
...

source: http://wiki.debian.org/BridgeNetworkConnections

By: arlen

arlen — Thu, 22 Mar 2012 10:18:20 +0000

it is very helpful and get it fixed.

Thanks

By: Paul

Paul — Fri, 27 May 2011 03:29:59 +0000

Thanks for the useful post. This scenario also applies to OpenVZ containers when configured with veth devices. An important thing to note (in my experience at least) is that whenever you make any changes to the bridge using brctl (deleting/adding interfaces) the MAC address selection happens again and will revert your previous "ifconfig" or "ip link set" commands. With OpenVZ, I get around this by adding "$ifconfig $VZHOSTBR hw ether $($ifconfig eth0 | awk '{print $5; exit}')" to the vznetaddbr script (called when starting a container if "CONFIG_CUSTOMIZED=yes" in $VEID.conf) and vps.umount (called when stopping a container).

Your post and the post at http://www.linuxweblog.com/blogs/sandip/20080814/bridge-networking-on-openvz-containers-using-veth-devices were both very helpful in helping me to find and solve a pretty tricky problem today.

-Paul

By: isido

isido — Mon, 02 May 2011 12:55:37 +0000

I'm wondering if this can be configured without specifying the mac address and instead of using something like bridge_hw `ip link show eth1 | awk '/ether/ {print $2}'` in the /etc/network/interfaces -file. It probably fails now, because eth1 is not yet configured when the command is executed

By: tudor

tudor — Mon, 14 Mar 2011 04:28:32 +0000

In reply to tudor. OK, IT works, I had a typo in address ! The address mac address you give MUST be one of your enslaved ethernet cards. This is probably for some sort of security reasons, so you can't spoof and create chaos in the network by artificially replicating the same mac. I mistyped a character to be sure of that :/ Thanks, nice "how-to".