I have a question on networking and initramfs interaction. I already posted this on the Ubuntu forums, but wondered if someone on this list might have more familiarity with the underpinnings of dropbear and initramfs. I'm decent with Linux but this is new territory for me.
Installing Ubuntu 12.10 server, 64 bit, on some new hardware. Working on using dropbear / ssh to remotely unlock LUKS volumes at boot, generally following the outline posted by hacksr at http://hacksr.blogspot.com/2012/05/ssh-unlock-with-fully-encrypted-ubuntu.html. The install is very basic at this point: an SSH server, apt-get update/upgrade complete, and a static IP address set for eth0 in /etc/network/interfaces. It boots quickly prior to installing dropbear. After installing dropbear, initramfs starts networking on bootup. By default, it uses DHCP. It is also possible to set a static IP. That much I have working, and can remotely ssh in when the server starts and is waiting for the luks passphrase. Thanks to the second script at the above how-to, I can also enter the unlock passphrase in the dropbear session and start the server. What I can't figure out, and haven't found a post anywhere that addresses this, is that once this process completes and the server continues to boot, the network remains somehow under "control" of initramfs. Boot process stops for several minutes "waiting for network configuration" in spite of the static IP settings for both initramfs and /etc/network/interfaces. Once it finally starts, any settings in /etc/network/interfaces are ignored. If the IP addresses don't match, I end up with the one in initramfs. If initramfs uses dhcp, I get that address once the server fully boots. * "service networking restart" changes nothing. * "ifdown eth0" says that eth0 is not configured. * "ifup eth0" returns "RTNETLINK answers: File exists. Failed to bring up eth0." * /run/network has only the loopback entries. There are no longer entries for eth0 or the static network directory. Am I missing a script in the /scripts/init-bottom or local-bottom where dropbear shuts down? Or is this expected behavior when initramfs uses the network at boot? - Paul
