I got a replacement board and the error seems to have gone. I did run iperf for over an hour and no hanging was detected. Looks like the board was faulty, leading to the exact same behaviour as described in the mentioned bug.
** Changed in: linux (Ubuntu) Status: Incomplete => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1604001 Title: igb: Detected TX unit hang To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1604001/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs