Note to self - running commands via the Switch User command - su

For reference, as I know I'll need this again before too long …

This is how I can stop the DB2 Administration Server and DB2 instance without needing to explicitly log in as a DB2 user: -

su - -c "db2admin stop" dasusr1

su - -c "db2stop" db2inst1

So that's all good then :-)