I and my colleagues deal with ubuntu images/restores and the current udev/iftab behaviour has caused us a fair bit of grief for the same reason.
Currently, a backup or image isn't usable by another machine without manually editing iftab. That isn't obvious to users, I think. One solution is to warn users. Another is to make iftab mac addresses advisory instead of required; so if the mac doesn't appear, udev ignores that line and reuses the name. Reasoning for that change is as follows: by the description here: http://www.ubuntuforums.org/showthread.php?t=128276&page=2&highlight=udev+iftab it looks like udev needs a list of active mac addresses from iftab; and iftab is only populated on install (dpkg --reinstall install udev, for example). It looks like the current behaviour is designed to preserve numbering for multiple interfaces if any of them are listed in iftab; permanantly reserving those numbers and allocating those which ARE NOT listed, in a way that doesn't conflict. If there are multiple interfaces, and only some are listed in iftab, the change I propose would mean that for interfaces that aren't listed, they would be renumbered if you unplug the interfaces that ARE listed in iftab. But if the goal is that all interfaces are listed in iftab, that shouldn't happen, right? It seems to me this would only happen if the user has multiple removable devices, which are removed on installation, and are then occasionally removed/reinstalled, but they need to have consistant IDs. But not if there's only a single removable device, such as a wireless card. I suspect it's a more likely situation for people to try installing an image onto a new machine. Isn't it? ** Tags added: eth0 iftab mac udev -- Dapper doesn't report iftab MAC address error https://launchpad.net/bugs/53936 -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
