The <Confluence_Install>/bin/start-confluence.sh script uses a variable, CONF_USER which is set in <Confluence_Install>/bin/user.sh.

To change the user the script will use to run Confluence,

1. Edit <Confluence_Install>/bin/user.sh:

# START INSTALLER MAGIC ! DO NOT EDIT !
CONF_USER="confluence" ##
# END INSTALLER MAGIC ! DO NOT EDIT !
export CONF_USER

2. Replace "confluence" with the user you would like to run Confluence.

3. When you start Confluence using start-confluence.sh the user you designated will be used.