Public bug reported: Upon upgrading from U18.04 to U20.04.2, the network interface names became unpredictable. They could be *any* of eth0, eth1, eth2 and ens2. Further inspection shows error messages like "systemd-udevd: eth1: Failed to rename network interface 3 from 'eth1' to 'ens2': File exists"
The installation is plain vanilla; in fact, the system had not been used at all yet. Neither of the files '/lib/udev/rules.d/75-persistent-net- generator.rules', '/etc/udev/rules.d/70-persistent-net.rules' or '/lib/udev/rules.d/71-biosdevname.rules' exist. On U18.04, 'ls /sys/class/net' yielded "enp5s0 enp14s0 enp9s0 lo". After the upgrade, it currently shows "ens2 eth0 eth1 lo". For each of these entries, 'udevadm test-builtin net_id $nic 2>/dev/null' gives the following: /sys/class/net/ens2 ID_NET_NAMING_SCHEME=v245 ID_NET_NAME_MAC=enx002481d13e60 ID_OUI_FROM_DATABASE=Hewlett Packard ID_NET_NAME_PATH=enp14s0 ID_NET_NAME_SLOT=ens2 /sys/class/net/eth0 ID_NET_NAMING_SCHEME=v245 ID_NET_NAME_MAC=enx001018b197dc ID_OUI_FROM_DATABASE=Broadcom ID_NET_NAME_PATH=enp5s0 ID_NET_NAME_SLOT=ens2 /sys/class/net/eth1 ID_NET_NAMING_SCHEME=v245 ID_NET_NAME_MAC=enx00101897069a ID_OUI_FROM_DATABASE=Broadcom ID_NET_NAME_PATH=enp9s0 ID_NET_NAME_SLOT=ens2 This seems to be a case where the naming scheme v245 should be replaced by v247, according to https://www.freedesktop.org/software/systemd/man/systemd.net-naming-scheme.html The situation does not change with passing "net.naming-scheme=latest" to the kernel. The installed version of udev is 245.4-4ubuntu3.4. Since this faulty behavior happened completely out of the blue on a practically pristine LTS installation, I hope to have some kind of solution similar to a backport. Thanks for comments! ** Affects: systemd (Ubuntu) Importance: Undecided Status: New ** Tags: net.naming-scheme udev -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1914884 Title: udev tries to assign identical name to multiple network cards To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1914884/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
