Re: mount(8) man page has wrong example for 'mount -t mfs'

[David Krause <openbsd@davidkrause.com>]

* Jonathan Thornburg <jthorn@aei.mpg.de> [040101 10:30]:
> In both OpenBSD 3.4-release (just installed from the CD) and -current
> on the web as of just now, the mount(8) man page includes the example
> 
> > For example, the mount command:
> > 
> >    # mount -t mfs -o nosuid,-N,-s=4000 /dev/dk0b /tmp
> > 
> > causes mount to execute the equivalent of:
> > 
> >    # /sbin/mount_mfs -o nosuid -N -s 4000 /dev/dk0b /tmp
> 
> Assuming the usual OpenBSD conventions, /dev/dk0b will be a swap
> partition, in which case, as was just pointed out to me in message
> <http://monkey.org/openbsd/archive/tech/0312/msg00184.html>, the syntax
> is wrong (and doesn't work any more as of 3.4).  According to that message,
> the correct syntax has   swap   instead of    /dev/dk0b   .
> 
> Since this is an   mfs   example, would it also be appropriate to add
> the   async   mount option?

I'm running 3.4-stable and have no problem using the syntax from your
original mail:

ender# cat /etc/fstab
/dev/wd0a / ffs rw,softdep 1 1
/dev/wd0b /tmp mfs rw,async,noatime,nodev,noexec,nosuid 0 0
/dev/wd0d /var ffs rw,nodev,nosuid,softdep 1 2
/dev/wd0e /usr ffs rw,nodev,softdep 1 2
/dev/wd0f /home ffs rw,nodev,nosuid,softdep 1 2

ender# mount -v | grep mfs
mfs:26692 on /tmp type mfs (rw, asynchronous, local, noatime, nodev,
noexec, nosuid, ctime=Mon Dec 15 22:41:04 2003, size=524160 1K-blocks)

If i add the exact example from your fstab it works also:
/dev/wd0b /usr/tmp mfs rw,nodev,async 0 0

ender# mount -v | grep mfs
mfs:26692 on /tmp type mfs (rw, asynchronous, local, noatime, nodev,
noexec, nosuid, ctime=Mon Dec 15 22:41:04 2003, size=524160 1K-blocks)
mfs:16440 on /usr/tmp type mfs (rw, asynchronous, local, nodev,
ctime=Thu Jan  1 11:58:33 2004, size=524160 1K-blocks)

However, the example in the mount(8) man page is indeed wrong.  The -N
option only exists for newfs, not mount_mfs.  If you remove -N and
change dk0b to wd0b it will work:

ender# /sbin/mount_mfs -o nosuid -s 4000 /dev/wd0b /usr/tmp
ender# mount | grep /usr/tmp
mfs:6382 on /usr/tmp type mfs (asynchronous, local, nosuid, size=2000
1K-blocks)

The fstab(5) man page also has a working example of /tmp mfs:
/dev/sd0b /tmp mfs rw,nodev,nosuid,-s=153600 0 0

I did notice you have a lot of memory.  What if you try to limit it with
-s?  Could be something caused by that possibly.

David