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”.
It’s amazing how many linux problems stem from ‘Redhat, however, found this solution too simple and instead devised their own scheme’. Just about every over complex, bloated bit of nonsense we have to fight with has the same genesis.
What I really don’t understand is why distro maintainers feel the need to actually go along with these changes. Like, sure, if this predictable interface naming thing worked as intended, I can definitely see how it can be useful for server administrators. You could just hardcode the automatic interface names instead of assigning them manually in
/etc/mactab. But why would the rest of us ever need this? Most personal machines have at most one wifi card and one ethernet device, sowlan0andeth0are perfectly predictable. And even if you have multiple wifi or ethernet adapters, your networking is probably handled by network-manager, so you never actually have to put interface names into config files. Why force enterprise-grade bloat on users who just want a simple desktop experience?As to why distro maintainers go along, if you had to vet every time the network stack updated and make sure it doesn’t break your custom solution to predictable naming, you’d probably just go along with it and let anyone that needed it devise and maintain their own solution. 99% of users won’t worry about it.