if SFTP binds mounts then that makes sense. Here is what happens...
zfs list
NAME USED AVAIL REFER MOUNTPOINT
StorPoolMmbr01 12.5T 2.79T 363K /StorPoolMmbr01
StorPoolMmbr01/ApplicationServerFS 465G 2.79T 465G /StorPoolMmbr01/ApplicationServerFS
StorPoolMmbr01/BackupDataFS 672G 2.79T 672G /StorPoolMmbr01/BackupDataFS
StorPoolMmbr01/DownloadsFS 192G 2.79T 192G /StorPoolMmbr01/DownloadsFS
StorPoolMmbr01/MediaAlbumsFS 386G 2.79T 386G /StorPoolMmbr01/MediaAlbumsFS
StorPoolMmbr01/MediaCollectionFS 9.56T 2.79T 9.56T /StorPoolMmbr01/MediaCollectionFS
StorPoolMmbr01/SoftwareFS 1.04T 2.79T 1.04T /StorPoolMmbr01/SoftwareFS
StorPoolMmbr01/UserDataFS 197G 2.79T 197G /StorPoolMmbr01/UserDataFS
I broke up everything into different datasets
when I see the root file system this is what I see...
rwxr-xr-x 4 root root 4096 Sep 30 21:11 sftp
drwxr-xr-x 24 root root 4096 Oct 1 08:06 sharedfolders
drwxr-xr-x 4 root root 4096 Oct 1 07:12 srv
drwxr-xr-x 9 root root 9 Sep 28 08:01 StorPoolMmbr01
dr-xr-xr-x 13 root root 0 Oct 1 12:49 sys
drwxrwxrwt 9 root root 180 Oct 1 14:50 tmp
drwxr-xr-x 11 root root 4096 Apr 4 2018 usr
drwxr-xr-x 13 root root 4096 Jun 19 2018 var
lrwxrwxrwx 1 root root 27 Sep 23 07:36 vmlinuz -> boot/vmlinuz-4.15.18-20-pve
lrwxrwxrwx 1 root root 27 Sep 23 07:36 vmlinuz.old -> boot/vmlinuz-4.15.18-20-pve
-rw-r--r-- 1 root root 932 Oct 1 08:36 webmin-setup.out
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As you can see StorPoolMmbr01 is the mount point of my ZFS pool.
These are the folders under StorPoolMmbr01.
drwxr-xr-x 4 root root 4 Sep 28 01:49 ApplicationServerFS
drwxr-xr-x 7 root root 7 Sep 28 02:10 BackupDataFS
drwxr-xr-x 5 root root 5 Sep 30 08:47 DownloadsFS
drwxr-xr-x 4 root root 4 Sep 28 02:18 MediaAlbumsFS
drwxr-xr-x 10 root root 10 Sep 28 02:19 MediaCollectionFS
drwxr-xr-x 3 root root 3 Sep 28 02:19 SoftwareFS
drwxr-xr-x 5 root root 5 Oct 1 08:06 UserDataFS
The problem is that when the machine is restarted the folders underneath UserDataFS and MediaCollectionFS are never empty on startup. When ZFS tries to mount the volume and all the datasets it fails on those two. I think this is because SFTP somehow puts folders under those that I have to delete. If those folders are left there bound then that makes sense, and would cause ZFS to fail to mount UserDataFS and MediaCollectionFS on startup. How would I know if SFTP is cleaning up during system shutdown? Perhaps there is something I can do to try and workaround. I don't want to start complicating things by using docker containers.