Karl O. Pinc wrote: >> https://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/ [...] >> Oh, looking at it again: maybe where it currently says >> >> <para> >> This should give enough information to devise a migration plan. >> (The <literal>udevadm</literal> output will include a fallback >> MAC-based name, sometimes needed for USB network hardware.) >> </para> >> >> We could fit in some sort of mention of ID_NET_NAME_ONBOARD as well? > > It would sure be nice to have an ordered list where the topmost > in the list which appears in the udevadm output is used: > > ID_NET_NAME_ONBOARD > ID_NET_NAME_PATH > ID_NET_NAME_MAC > > And so forth. I don't even know if this makes sense but > without some guidance there's just no way for > the reader to know what name the kernel will use.
Yes, if you study the freedesktop.org page (which unhelpfully leaves out the actual ID_NET_NAME_ terms) you'll see that by default it's ONBOARD (eno1) SLOT (ens1) PATH (which may look like anything from enp0s1f1 to eth0) MAC (enx101010101010) *except* that there are several ways of overriding these defaults, and one of them may have been set up without the user knowing about it (this whole thing is after all being set off by the fact that they've got a "legacy" .rules file). Then again Google also tells me horror stories of firmware/kernel/udev interactions that unexpectedly resurrect different name schemes. And this is just ethernet NICs! I don't think it's realistic to expect that the Buster release-notes could contain an accurate, user-friendly guide covering everything that people need to know, even if they're running a laptop with a phone dongle, a VM with an out-of-date kernel, or a server with infiniband hardware where the previous sysadmin set up crazy .rules files! We're going to have to leave corner cases to external sources, and it isn't clear to me how common even things like ONBOARD and SLOT names are. After sleeping on it, here's an attempt to stuff more advice into the above paragraph: <para> This should give enough information to devise a migration plan. (If the <literal>udevadm</literal> output includes an <quote>onboard</quote> name, that takes priority; MAC-based names are normally treated as a fallback, but may be needed for USB network hardware.) </para> -- JBR with qualifications in linguistics, experience as a Debian sysadmin, and probably no clue about this particular package