Context for newbies: Linux refers to network adapters (wifi cards, ethernet cards, etc.) by so called “interfaces”. For the longest time, the interface names were assigned based on the type of device and the order in which the system discovered it. So, eth0, eth1, wlan0, and wwan0 are all possible interface names. This, however, can be an issue: “the order in which the system discovered it” is not deterministic, which means hardware can switch interface names across reboots. This can be a real issue for things like servers that rely on interface names staying the same.

The solution to this issue is to assign custom names based on MAC address. The MAC address is hardcoded into the network adaptor, and will not change. (There are other ways to do this as well, such as setting udev rules).

Redhat, however, found this solution too simple and instead devised their own scheme for assigning network interface names. It fails at solving the problem it was created to solve while making it much harder to type and remember interface names.

To disable predictable interface naming and switch back to the old scheme, add net.ifnames=0 and biosdevname=0 to your boot paramets.

The template for this meme is called “stop doing math”.

  • @[email protected]
    link
    fedilink
    1
    edit-2
    5 months ago

    Personally I’d do away with NetworkManager too and just configure the interfaces directly

    Connman and iwd have nice graphical interfaces btw. I got that route after nm disbehaved and i couldn’t figure out why (same for systemd and s6/dinit after systemd-dnsd threw a fit).

    • @anyhow2503
      link
      25 months ago

      I tried using connman to setup a wireguard connection once. It was not a good experience and ultimately led nowhere, due to missing feature support.