Help with running a script at shutdown and make it run first before other services

[David Elie-Dit-Cosaque <deliedit@xxxxxxxxxx>]

Hi All,

I am trying to create a systemd service that would execute a script at shutdown before any other services start receiving shutdown notifications. I came up with this:

[Service]
Type=oneshot
RemainAfterExit=true
ExecStart=/usr/bin/true
ExecStop=/usr/local/bin/myscript.sh
[Install]
WantedBy=multi-user.target

The script does run after shutdown is initiated but since it relies on other services which are also shutting down, it fails. Is there a way to order the shutdown so that  myscript.sh is completed first before continuing with the shutdown? 

Thanks!

David.