[systemd-devel] How to express that a device listed in /etc/crypttab depends on a mount point

[Andrei Borzenkov]

25.09.2024 18:28, aplanas wrote:
> Hi!
> 
> An user have /home in a different encrypted partition via pcrlock. After
> the initrd, during the normal boot process, the systemd-cryptsetup
> generator is reading this file to open the devices in /dev/mapper/$name.
> But this is happening before /var gets mounted, and this contains the
> pcrlock.json file requires to unlock the home device.
> 
> Is there a way to indicate this dependency for the generator, as a
> "RequiresMountsFor=" for .mount services or x-systemd.requires= in
> fstab?

This dependency only exists for pcrlock and only if there are reasons to 
have pcrlock.json in /var and not in /etc by default.

RequiresMountsFor sounds wrong here (normally systemd-cryptsetup falls 
back to interactively asking for passphrase), but WantsMountsFor=/var 
looks suitable. And I would actually expect 
systemd-cryptsetup-generator to add it automatically. This should not 
involve manual configuration.