I am new to cacti. I got cacti running and wanted to use the Advanced Ping Templete. It works fine but I want to change the Interval to 30 seconds instead of the 5 minutes. Can't find where I can change this interval.
AFAIK, Cacti minmum interval is 1 minute, and you have to change that in the configuration and the poller cron job.
You can install a real-time plugin which can poll faster, but it uses a temp RRD files.
EDIT: I know that Zabbix support customized polling intervals down to 1 sec, and you can set this per item and not system wide (unlike cacti).