Relationship between cryptsetup and ZBM? (How to eliminate cryptsetup error messages during initramfs updates?)

[Binarus]

Dear all,

although I'm using it since quite a time on multiple machines, I am still excited about ZBM and about how super responsive the developers and the community are. At my very first try, I had found a small glitch that had been fixed in no time, and I never had a real problem since.

However, there is one little thing that I'd like to solve now. Every time my systems (all Debian bookworm) generate the initramfs, I get messages like the following in the output:

cryptsetup: ERROR: Couldn't resolve device rpool/sys-gaia
cryptsetup: WARNING: Couldn't determine root device

I am using root on ZFS, if that matters.

While I know that I can safely ignore these messages, I'd like to eliminate them. Apparently, the root cause is the package cryptsetup-initramfs which eventually got installed when preparing my systems for ZBM the first time. To install ZBM, the manual recommends the tutorial I was following at that time included the installation of the cryptsetup package (which probably caused cryptsetup-initramfs to be installed as well). Unfortunately, I can't find that tutorial any more.

The obvious solution to eliminate the above error messages would be to uninstall cryptsetup-initramfs. However, this is not my field, so I am afraid that I'll break my systems if I do that.

Therefore, I'd like to learn why whether ZBM really needs cryptsetup at all, and if I can indeed safely remove cryptsetup-initramfs.

Thanks a lot in advance!

[zdykstra]

ZFSBootMenu doesn't actually support cryptsetup (or LUKS) at all right now. There shouldn't be any complications removing the cryptsetup-initramfs package from your system.

[Binarus]

Thank you very much!

In the meantime, motivated by your comment, I have removed the cryptsetup-initramfs package. This indeed made the error messages go away and did not cause side effects.

I guess I'll now close this "issue".

Thanks again for ZBM! It is a real life saver.

[ahesford]

What manual recommends adding the cryptsetup module to the initramfs image?

[Binarus]

@ahesford

No manual directly recommends adding the cryptsetup module to the initramfs. However, when I tried to install ZBM for the very first time a while ago, there was a recommendation to install the cryptsetup package as a prerequisite for ZBM. Actually, I can't find this reference any longer, but there are a few scripts that are meant to simplify ZBM installation and that still install cryptsetup; examples are

https://github.com/Sithuk/ubuntu-server-zfsbootmenu/blob/main/ubuntu_server_encrypted_root_zfs.sh
https://gitlab.com/-/snippets/2099921

I didn't look thoroughly into these sources and thus don't know why exactly these scripts install cryptsetup. But it is clear that the scripts a) aim at installing ZBM and that they b) pull in the cryptsetup package. It seems that there is some sort of slight relationship between cryptsetup and ZBM.

Coming back to the subject, as mentioned above, when installing ZBM the very first time, I followed a procedure (probably in some wiki) that contained the following line which also caused cryptsetup to be installed:

apt-get install -y ... cryptsetup ...

I believe that this in my case could have pulled in cryptsetup-initramfs as well.

But the "problem" is solved in the meantime. I have removed the cryptsetup-initramfs package. This made the error messages go away and did not cause any side effects AFAICT.

Thank you very much for asking. I have updated my first post accordingly.

[Binarus]

The issue has been resolved. As it seems, ZBM neither needs cryptsetup nor cryptsetup-initramfs, and since having removed the latter, no more error messages have appeared when generating the initramfs. I did not observe negative side effects.