For about a year, my unraid server always starts a parity check after normal shutdown/reboot(e.g. when i shutdown through webGui). I used to think perhaps that's because i am running too many containers so the shutdown process timed out. 

 

But today i check the logs when unraid is shutting down:

Stopping md/unraid driver:
/etc/rc.d/rc.6: line 273: /usr/local/sbin/mdcmd: No such file or directory.
Unclean shutdown - Cannot stop md/unraid driver

line 273 of /etc/rc.d/rc.6 is: /usr/local/sbin/mdcmd stop 

here is the relevant part in /etc/rc.d/rc.6, the line 273 is the 4th line in the code block

# limetech - shut down the unraid driver if started
if /bin/grep -qs 'mdState=STARTED' /proc/mdstat ; then
  echo "Stopping md/unraid driver:"
  /usr/local/sbin/mdcmd stop
  if ! /bin/grep -qs 'mdState=STOPPED' /proc/mdstat ; then
    echo "Unclean shutdown - Cannot stop md/unraid driver"
  else
    # we have to mount /boot again
    if ! /sbin/mount -v /boot ; then
      echo "Unclean shutdown - Cannot remount /boot"
    else
      /bin/rm -f /boot/config/forcesync
      /sbin/umount /boot
      echo "Clean shutdown"
    fi
  fi
fi

 

The following is the auto-generated diagnostics when shutting down, and the actually photo of the screen when shutting down(which might be helpful)

tower-diagnostics-20230728-1800.zip

Have you tried the steps for troubleshooting Unclean shutdown that are covered here in the online documentation accessible via the ‘Manual’ link at the bottom of the GUI or the DOCS link at the top of each forum page.

I suggest several things:

• Update all your dockers as they are out of date.
• Upgrade to 6.12.3.  A docker stopping issue has been fixed that might be what's happening to you.
• Check the Settings->Docker "Docker stop timeouot" and see if that is enough time to shut down your dockers.