Installing biosdevname should warn about required network configuration

[Nelson Minar]

Installing biosdevname can result in a system that will not have working networking on reboot. I think there should be a warning / dialog when the package is installed that warns users they need to do further system configuration after installation.

biosdevname creates a udev rule /lib/udev/rules.d/71-biosdevname.rules. This can override any existing udev naming for an ethernet device, particularly one in /etc/udev/rules.d/70-persistent-net.rules that comes from a legacy install. In practice, what this means is that after installing biosdevname the Ethernet device may be named something like /dev/p4p1 instead of /dev/eth0. After installation the user has to manually edit /etc/network/interfaces to have a working network on reboot.

I believe the code is all working correctly, but it'd be a kindness if the biosdevname installer detected the potential system breakage and warned the user. I don't believe there's any warning at all that installing this package can break the system at reboot.

(My story: I upgraded a working Ubuntu 10.10 system to 14.04 via do-system-upgrade. Then I stupidly and blindly installed biosdevname because some other Ubuntu 14.04 new install I had had that package. When I rebooted, I could no longer access my Ubuntu box over the network. Since the system was 1500 miles away and without a network console, that was a bit awkward.)

$ lsb_release -rd
Description: Ubuntu 14.04.1 LTS
Release: 14.04

$ apt-cache policy biosdevname | grep Installed
  Installed: 0.4.1-0ubuntu6.1

See also: https://bugs.launchpad.net/serverguide/+bug/1312785

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.