[dm-crypt] Help: after crypttab modify > begin: waiting for root file system

[Tommaso <elisapippo@tiscali.it>]

Sorry for my poor english and for the not-so-clear topic, I hope someone
can help me because I'm in serious trouble :(

I run (ehm... I was running :( ) a headless debian lenny server with
encrypted LUKS filesystem. After I made an apparently harmless modify to
the crypttab file I can no longer boot the system. At startup I get the
message:

    Begin: waiting for root file system...


And all is hanged up. I have a plaintext /boot partition with the
bootloader (grub), while everything else is encrypted. My /etc/crypttab
file was something like this:

    lg0-lv0_crypt /dev/mapper/lg0-lv0 none luks


so that at boot time it was necessary to manually insert a passphrase to
unlock the filesystem (lg0-lv0_crypt is mounted as / on fstab). Now, I
must leave the place where the server resides for some weeks, so I
decided to temporarily override this behaviour with a cleartext key file
to avoid problems due to accidental rebooting. So I did:
1) put a random key_temp file in /boot with 600 permission
2) cryptsetup luksAddKey /dev/mapper/lg0-lv0 /boot/key_temp
3) edited /etc/crypttab to look like this:

    lg0-lv0_crypt /dev/mapper/lg0-lv0 /boot/key_temp luks

4) update-initramfs -u ALL

but when I rebooted... all was hanged up as I said before. I can't
manage even how to undo my changes now.

Can you help me please? U_U