When the rc script is in place, the server can be started with /etc/rc.d/proftpd start (/etc/init.d/proftpdstart on Debian).
Stopping the server
To shut the FTP daemon down, run /etc/rc.d/proftpd stop.
Temporarily suspending the server
With /etc/rc.d/proftpd suspend you can stop ProFTPD from accepting new connections. Users who try to log in will be greeted with a banner telling them that the server is down for maintenance. To resume normal operations, run /etc/rc.d/proftpd resume.
While troubleshooting or writing the ProFTPD configuration file, it is often useful to get some extra information about what is going on. proftpd -vv will print out some version information, proftpd --nodaemon will run the daemon without becoming a background process, and proftpd -t will check the syntax of the current configuration file. Output verbosity can be increased by running ProFTPD like this: proftpd -d9. The options -d0 to -d9 can be combined with the other options.