Looks like this bug fell through the cracks. It's still valid, and easy to reproduce in a VM:
$ multipass launch daily:xenial -n x1 $ multipass exec x1 cat /sys/class/net/ens3/speed -1 And if you have munin-node installed: $ multipass exec x1 sudo munin-run if_ens3 config|tail -n 3 up.max -1000000 up.info Traffic of the ens3 interface. Maximum speed is -1 Mb/s. down.max -1000000 With the fix, it asks you to install ethtool or another such tool: up.info Traffic of the ens3 interface. Unable to determine interface speed. Please install ethtool, wireless-tools, mii-tool or whatever is appropriate for the interface. But that also reports unknown speed, probably because it's a vm virtio device. But the speed can be set manually: sudo ethtool -s ens3 speed 1000 duplex full In any case, I guess unknown speed is better then a negative one, right? -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1673357 Title: Munin core plugin "if_" doesn't work To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/munin/+bug/1673357/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs