Open source tool to monitor your servers and websites
...To check your IMAP service for example, enter port 143.
For websites you can enter a link and it will check the HTTP status code. If the HTTP status code is in the 4xx range or a timeout, it means an error occurred and the tool will start sending out notifications. You can also set a regular expression to match for content on the page itself.
Each server has its own settings regarding notification. You can choose for email, text message (SMS) and Pushover.net notifications.
For more info please visit http://www.phpservermonitor.org
...Any device's ports added to it will be logged, without averages to save space, while at the same time keeping relevant details for indefinite time at low requirements on space (e.g. keeping in/out/error counters of a router interface, at 1min intervals, for a whole month only comes in at ~130k)