On Wed, 11 Oct 2017 09:08:15 +0200, Alessandro wrote in message <[email protected]>:
> Il giorno Tue, 10 Oct 2017 22:25:23 -0500 > John Morris <[email protected]> ha scritto: > > > On Tue, 2017-10-10 at 01:49 +0200, Alessandro Selli wrote: > > > >> By the manual, the correct solution in configuring Grub as to > >> pass the kernel these parameters: > >> > >> biosdevname=0 net.ifnames=0 > > > > Those fix similar problems but not exactly the same ones. > > Agree. udev rules confer a given piece of hardware a given name. > Those kernel parameters instruct the kernel not to let network > interfaces be renamed by userland. > > > The udev > > persistent rules get you when you move an image from one machine to > > another or swap out failed hardware and suddenly you have no network > > because eth0 suddenly became eth1. > > Well, if you had a /etc/udev/rules.d/70-persistent-net.rules file > that renamed a network interface identified by its MAC address eth0 > and you swapped that card for a new one, then the new one is going to > get a different name because eth0 was already taken. If you used > those kernel parameters instead it would be named eth0. Which is > what you'd expect if it was the only ethernet card on board. ..then it would be possible to simply count ethernet etc cards and check whether or not there are other changes and whether or not the main board is e.g. a known laptop type of mainboard. ..once such facts are collected, it's possible to pop up a wee list of questions such as "New wifi card?" to "You moved this disk into a new laptop?" and make use of the answers given by the user. > > And as I noted, not only network > > device names but CD drives as well are impacted. > > I think for CDs and DVDs the biosdevname=0 parameter suffices. It > used to be all it was needed to prevent networking gear from being > renamed, but at some point they added the net.ifnames=0 parameter > that is specific to ethernet cards. > > > The fixes you suggest > > solve the equally annoying problem of eth0 or wlan0 unexpectedly > > turning into a string of gibberish after an upgrade. > > Pretty annoying, agree. That's the reason I enquiried about the > possible ways to prevent the renaming from happening. > > > They are turning everything into a UUID or similar string of > > untypable gibberish. It is almost like they don't want you to use > > the command line directly anymore. Nah, that couldn't be it, > > right? > > I don't think that's the reason, many critical Linux systems are > run and managed without a GUI, just think of supercomputers, > clusters, IoT and embedded devices. Carrying around a complex device > name is not such an issue, you just export an ETH0 variable with it's > name and use $ETH0 in place of eth0 on the commands you type. I > still do prefer typing just eth0, I'm such a lazy sysadmin! :-) > > > Alessandro > _______________________________________________ > Dng mailing list > [email protected] > https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng -- ..med vennlig hilsen = with Kind Regards from Arnt Karlsen ...with a number of polar bear hunters in his ancestry... Scenarios always come in sets of three: best case, worst case, and just in case. _______________________________________________ Dng mailing list [email protected] https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
