First, configure user and passwords

To add/edit user, use burg-adduser, for example:

sudo burg-adduser --super admin
sudo burg-adduser user1

The --super option is used to specify super user.

To remove user, use burg-deluser, for example:

sudo burg-deluser user1

The password is stored in /etc/default/burg-passwd.

Second, setup GRUB_USERS variable in /etc/default/burg

Here is an example:

GRUB_USERS="*=user1,user2:ubuntu=user1:windows="

This means user1 can boot Ubuntu, no password is needed for Windows, user1 and user2 can boot other OS besides Ubuntu and Windows. Superusers can boot any OS and use system-wide hotkeys like `c' to enter console mode.

You can also use different setting for normal and rescue boot items, add to class name to indicate rescue items, for example:

GRUB_USERS="ubuntu=user1"

user1 can use both normal and rescue boot items.

GRUB_USERS="*ubuntu=user1"

Anyone can use normal boot item, user1 can use rescue boot item.

GRUB_USERS="ubuntu=user1:*ubuntu=user2"

User1 can use normal boot item, user2 can use rescue boot item.

Superusers can use all items.

Finally, generate burg.cfg with update-burg

sudo update-burg

You can use burg-emu to check the configuration before reboot:

sudo burg-emu