Proper order of unmount for zfs partition / dmcrypt

[uint]

Hi! I have a setup with two disk partitions encrypted with dmcrypt (LUKS), and over them there's a zfs mirrored pool. I also have OpenRC.

At the system boot, the startup order is correct: first I get prompted for the passphrases of the encrypted partitions, then dmcrypt unlocks them, then zfs imports the pool and mounts the partition to the file system.

However, at shutdown it seems that zfs does not unmount its partition, either in time, or at all. This leads to the shutdown log having dmcrypt complaining that encrypted devices cannot be unmounted (as they are busy). I don't have the log at hand, as this normally happens after the syslog-ng shutdown.

This does not seem to do much harm, but still looks messy, and I'd like to set up the correct shutdown order, where:
- zfs partition is unmounted from the fs
- zfs stops the pool (however it calls this operation)
- dmcrypt stops the underlying encrypted partitions

But I'm not sure how to do that, and specifically what controls the order in which OpenRC stops services.
I tried to set

[Hu]

Welcome to the forums.

Could you provide a bit more information about the environment? Specifically, is the affected ZFS for critical filesystems like /, for non-critical filesystems like /home, or both? Is the passphrase prompt at boot handled by the initramfs or by the Gentoo dmcrypt initscript? Can you show us /etc/fstab and the output of grep '^[^#]' /etc/conf.d/dmcrypt (non-blank non-comment lines, since there are a lot of stock comments we don't need here)? Mask out any serial numbers or similar if you like. I only want to see how many devices are in use, and their device-mapper names once unlocked.

[uint]

Thank you! ZFS is used for /home and some other non-critical data, so not / . Passphrase is handled by the dmcrypt initscript, not initramfs.

/etc/fstab does not mention the ZFS partition (or underlying partitions) at all - it is mounted by the zfs initscripts. It has some generic partitions like / , /boot , etc. Removing entries for devices that are not attached by default, fstab is like this:

[Hu]

I am not familiar with ZFS or its unusual non-fstab-based unmounting here. Can you manually transcribe the error when the unmount fails?