Re: Snapdir of Nullfs-mounted Dataset incomplete in Jail

From: James Gritton <jamie_at_freebsd.org>
Date: Thu, 16 Nov 2023 18:35:03 UTC
On 2023-11-16 06:22, Matthias Petermann wrote:
> Hello everyone,
> ...
> Here's the problem: Snapshots are continuously created by Sanoid from
> the host. Over time, I now get different directory listings of snapdir
> depending on where I list it from: when listing from the host at
> /zroot/data/shares/.zfs/snapshot, everything is complete. In the Jail
> at /shares/.zfs/snapshot, the newer snapshots are missing.
> 
> If I then go to the host and execute the following:
> 
> ```
> % doas ls -lah /zroot/data/shares/.zfs/snapshot/*
> ```
> 
> ...I get all the snapshots with sub-directories listed as expected.
> 
> Surprisingly, after that, I can also see the snapshots from within the 
> Jail.
> 
> A similar issue is discussed in [1] and [2].
> 
> Where is my mistake in thinking?

No mistake in thinking.  I don't know what's going on there, but it's 
definitely not expected behavior.  If I knew ZFS better I could say for 
whether it was truly a bug, though I suspect it is.

- Jamie