Odd "phantom MFS mountpoint" issue

[Michael Proto]

H. Wade Minter wrote:
> I've got a 5.4-RELEASE-p9 system that I was doing some memory filesystem 
> testing on.  I'm seeing something odd, though - a small MFS partition 
> mounted over top of /tmp that I can't get rid of.
> 
> Here's the system now:
> 
> [minter at carlton mrvoice]$ mount
> /dev/ad0s1a on / (ufs, local, soft-updates)
> devfs on /dev (devfs, local)
> /dev/ad0s1d on /tmp (ufs, local, soft-updates)
> /dev/ad0s1f on /usr/www (ufs, local, soft-updates)
> /dev/ad0s1e on /var (ufs, local, soft-updates)
> /dev/md0 on /tmp (ufs, local)
> 
> There's no md0 line in /etc/fstab:
> 
> [minter at carlton mrvoice]$ cat /etc/fstab
> # Device                Mountpoint      FStype  Options         Dump 
> Pass#
> /dev/ad0s1b             none            swap    sw              0       0
> /dev/ad0s1a             /               ufs     rw              1       1
> /dev/ad0s1d             /tmp            ufs     rw              2       2
> /dev/ad0s1f             /usr/www                ufs     rw              2 
> 2
> /dev/ad0s1e             /var            ufs     rw              2       2
> /dev/acd0               /cdrom          cd9660  ro,noauto       0       0
> 
> I can see the md0 device with mdconfig:
> 
> [root at carlton ~]# mdconfig  -l
> md0
> 
> I can stop all activity on /tmp, unmount it, and do mdconfig -d -u 0 to 
> delete the resources.  However, when I reboot the system, the mountpoint 
> is back.  I can't tell where the system is getting that from.
> 
> How should I remove this mfs mountpoint permanently to get the disk-based 
> /tmp back?
> 
> --Wade

Do you have tmpmfs defined in /etc/rc.conf? If tmpfs is enabled there it
will create a /tmp mfs as you are indicating.


-Proto