ZFS Default location of zpool cachefile undocumented?

[Mjölnir]

Dear ZFS gurus,

before filing in a bug report, I'd like to make sure that I'm not missing a piece of documentation.
I couldn't find any documentation about the default location of the system's zpool cachefile yet, which would mean this is a RTFSD bug ("read the f*g ^H^H^H fine source, dude!"), which, as you can read from my status, makes me angry...

P.S. I know now where it is, but only by consulting external resources, i.e. a quick search in this forum.

 

[T-Aoki]

FYI: Read /etc/rc.d/zpool.

 

[Mjölnir]

FYI: Read /etc/rc.d/zpool.

This is RTFSD and not documentation. Docs are the manpages, since they are installed on most systems, and optionally the handbook.

 

[Mjölnir]

The next questions derive:

• are /boot/zfs/zpool.cache and /etc/zfs/zpool.cache hardlinked to the same file, is one a symlink to the other, or are they two distinct files?
• How can I create these files? Simply by touch(1)'ing an empty file? When I import a zpool with zpool import -c /etc/zfs/zpool.cache, I get an error:
  

  failed to open cache file: No such file or directory
  cannot import 'xyz': no such pool available

  (and at least the 2nd line is not true).

 

[T-Aoki]

Well, ZFS implementation of currently supported releases are OpenZFS and upstream has this.

 

[T-Aoki]

The next question derives: are /boot/zfs/zpool.cache and /etc/zfs/zpool.cache hardlinked to the same file, is one a symlink to the other, or are they two distinct files?

/boot/zfs/zpool.cache was the previous default that pre-OpenZFS (aka ZoF: ZFS on FreeBSD) implementation used, and kept for compatibility.

 

[Mjölnir]

Well, ZFS implementation of currently supported releases are OpenZFS and upstream has this.

That OpenZFS docs are 99% (or more) Linux'ish, so there's always uncertainty if the informations therein aply to FreeBSD, too, or if there're slight but important differences to the behaviour implemented on FreeBSD.