freebsd stable - Jul 2015 - jail: /etc/rc: cannot create /dev/null: Operation not supported

FreeBSD 10.2-PRERELEASE #0 r284949

The jail can be started, but when /etc/rc is executed:

root at mar:/ # sh -x /etc/rc
+ stty status ^T
/etc/rc: cannot create /dev/null: Operation not supported
+ trap : 2
+ trap 'echo '\''Boot interrupted'\''; exit 1' 3
+ HOME=/
+ PATH=/sbin:/bin:/usr/sbin:/usr/bin
+ export HOME PATH
+ [ '' = autoboot ]
+ autoboot=no
+ _boot=quietstart
+ /sbin/sysctl -n vfs.nfs.diskless_valid
/etc/rc: cannot create /dev/null: Operation not supported
...

I have done the procedure several times before but never saw this one  
before and don't know how to get around it.

Ideas anyone? Any recent changes that can show up like the above?

Thanks!

//per

On 2015-07-15 13:52, Per olof Ljungmark wrote:
> FreeBSD 10.2-PRERELEASE #0 r284949
> 
> The jail can be started, but when /etc/rc is executed:
> 
> root at mar:/ # sh -x /etc/rc
> + stty status ^T
> /etc/rc: cannot create /dev/null: Operation not supported
> + trap : 2
> + trap 'echo '\''Boot interrupted'\''; exit
1' 3
> + HOME=/
> + PATH=/sbin:/bin:/usr/sbin:/usr/bin
> + export HOME PATH
> + [ '' = autoboot ]
> + autoboot=no
> + _boot=quietstart
> + /sbin/sysctl -n vfs.nfs.diskless_valid
> /etc/rc: cannot create /dev/null: Operation not supported
> ...
> 
> I have done the procedure several times before but never saw this one
> before and don't know how to get around it.
> 
> Ideas anyone? Any recent changes that can show up like the above?
> 
> Thanks!
If it's trying to create /dev/null, I assume that the jail's /dev
isn't
mounted when /etc/rc is running.  Do you have mount.devfs set in the
jail.conf, or jail_foo_devfs_enable in rc.conf (depending on your
configuration)? For that matter, can you tell if the jail's /dev is
mounted?

- Jamie