network shares hang on restart / shutdown - consequence: hard shutdown required

Hi,

If I have mounted network shares (nfs, nfs4, cifs), these are unable to be unmounted / re-mounted as read during shutdown / restart, consequently the shutdown process hangs and I need to do a forced shutdown. The reason is that in /etc/runit/3 the network services are taken offline before before the drives are unmounted / re-mounted as read occurs.

I've created my own /etc/rc.pre-shutdown script (below) that is called by /etc/runit/3 before the services are closed that unmounts / re-mounts as read the network shares. This works.

Apologies if I've missed an obvious option / setting that renders my "fix" not needed, I'm just an enthusiastic Linux user, as opposed to developer.

Hope this is useful for someone.

Rob

echo "   trying to unmount network shares..."

umount -a -r -t nfs,nfs4,cifs

if grep -qs -e 'nfs ' -e 'nfs4 ' -e 'cifs ' /proc/mounts; then
   echo
   echo "...... failed to unmount network some network shares ......"
   rem_shares=$(grep -e 'nfs ' -e 'nfs4 ' -e 'cifs ' /proc/mounts)
   if echo $rem_shares | grep -qs 'rw,'; then
         echo "failed to mount read only as well"
         echo "will attempt forced, lazy unmount"
         echo "if this hangs then will need to hard shutdown..."
         umount -a -f -l -t nfs,nfs4,cifs
   elif echo $rem_shares | grep -qs 'ro,'; then
         echo "shares were mounted read only instead."
         echo "hopefully this is ok. If hangs...hard shutdown required"
   else
         echo "I should not be here..."
   fi
   echo
fi

Start by reading /etc/runit/3 and the reported /etc/rc.pre-shutdown script. Reproduce shutdown with nfs, nfs4, or cifs mounts and trace the ordering of service shutdown and mount handling. Done means network shares are unmounted or remounted read-only before shutdown completes without requiring a forced power-off.