autounmount NFS. Entry in /var/db/mounttab remains.

I have used autofs to automatically mount/unmount NFS since FreeBSD 10.3 (server and client 11.1 now) and have since then experienced problems with autounmountd not removing entries made by automount from /var/db/mount(d)tab.

When mounting the NFS manually mount -t nfs /mnt/ and then unmounting it with umount /mnt/ it works.
Entries in /var/db/mounttab on the client and /var/db/mountdtab on the server get created and removed.

With autofs on the client, those entries get created but they are never removed by autounmountd so they pile up in the files every time mount/unmount event happens.

I have debugged that like crazy with all involved services in debug-mode but couldn't find any sign of map type or mount-options would make a difference.

Last year, when my client was running Debian the entry from /var/db/mountdtab on the NFS server got reliable removed when autofs unmounted NFS.

Could it be a bug?
There is this Thread 61251 about AutoFS going on. My experience with it says it still do some annoying things.

If you do need the NFS share permanently mounted or do not mind to have it permanently mounted, you can mount it from /etc/fstab. See HERE.
Hei lebarondemerde,
Yes, I have read that thread before. Sadly I haven't seen anyone ever posting his experience who uses autofs to mount NFS.

I had NFS mounted permantly before, but when I startet using it with autofs (server running FreeBSD 10.3 and client Debian 8 at that time) I made a cron job that shut down the server after 10pm when there where no active NFS mounts. That's not working anymore.