I have a Debian 7.4 (stable) based server configured to use an encrypted (RAID1 + LVM) root partition (/boot is un-encrypted regular partition) to which I installed dropbear SSH server so I can remotely enter the LUKS encryption passphrase.
In addition to the root partition/volume I have other RAID1+cryptsetup+LVM volumes that I would like to be able to open with the same passphrase. I googled and found out I can use the script
/lib/cryptsetup/scripts/decrypt_keyctl to cache passphrases and open multiple volumes with the same passphrase. But how do I use this script with the passphrase entered in initramfs stage?