[389-users] create pin.txt file

HI I have already installed dirsrv and its running in production with ssl certificate on. when i restart dirsrv , its ask to provide the pin for the token. how can i create the pin.txt with password so that dir server starts automatically without providing the pin ?? i tried to create here , but seems did not work, /etc/dirsrv/slapd-ldap/pin.txt do i have to add anything special to create the file ?? any help will be really appreciated. Thanks