Can Grub2 multi-boot LUKS/LVM distros with only one boot partition?

There are many tutorials on the internet for multi-booting unencrypted distros using a single boot partition and chainloading. For example, booting 145 OSes.

Likewise, there are tutorials for multi-booting distros inside LUKS/LVM if multiple (unencrypted) boot partitions are used, by having the main bootloader chainload the bootloaders in the other unencrypted boot partitions. For example, multi-boot on LUKS.

But I have not been able to find any information about multi-booting with these constraints:

• Only one (or none) unencrypted boot partitions


• No external USB keyfile needed


• No manual steps, other than selecting the distro to boot, and entering the LUKS passphrase (only once)

Is it possible, and if so, how?

The partition arrangement I'm thinking of is:

• sda1, boot partition


• sda2, LUKS container

The LUKS container is managed by LVM:

• swap, shared among all distributions


• [ home, shared among all distributions ]


• root1, main distribution, mounting sda1 as /boot


• root2, distribution 2, including encrypted /boot


• root3, distribution 3, including encrypted /boot


• etc.

The closest information I've been able to find has a lot of manual steps: only bootloader unencrypted.