Hey @Jammie, you can use the check_ftp plugin for this.
The commands.cfg file contains a command definition for using the check_ftp plugin, which looks like this:
define command {
command_name check_ftp
command_line $USER1$/check_ftp -H $HOSTADDRESS$ $ARG1$
}
A simple service definition for monitoring the FTP server on host would look like this:
define service {
use generic-service ; Inherit default values from a template
host_name remotehost
service_description FTP
check_command check_ftp
}