I have three fancy devices which support Link Aggregation Groups which connect to each other. Expecting a large amount of traffic regularly flowing between them means I have an excuse to learn about this and get the nodes setup. There are multiple implemenations of LAG referred to as modes. I can see use cases for all of them however I am most interested in mode 4 which supports fault tolernce in failure modes while also allowing full resource utilization in optimal operating conditions. This means I will have a 2Gbps link between each of the devices. Most likely I will not saturate this however it will still be fun to learn. Anyway, unused hardware is wasted hardware and not doing this means I have excess ethernet ports :-).

The gist to get this setup seems to be the following:

  • Ensure the bonding kernel module is loaded. This can be confirmed by lsmod |grep -i bonding.
  • Create a new bond{i}.
  • Attach the actual ethernet devices to the interface
  • Verify via cat /proc/net/bonding/bond0
  • Profit

This Rackspace article looks great for the InitD folks, however the system I am currently working against is a SystemD based setup. Although poorly formatted a Manjaro article looks like a good start.

To get started loading the module is easy this time: modprobe bonding. The module definitely creates /proc/net/bonding and we can verify there are no bonds yet. Well it looks like I was a bit hasty. Upon further investigation Ubuntu is still using NetworkManager on the 18.10 release. I’ll need to use that.

I was not able to get the bonding0 device to exist. I tried the echo +foo >/sys/class/net/bonding_masters however this resulted in repeated rejections. I will have to approach this more gingerly in the future instead of taking the whole node offline due to optimism.


  • sudo ifdown -a will shutdown all network interfaces
  • sudo ifup -a will bring the interfaces all back up.