PRTG Network Monitor runs 24/7 on a Windows-based (including virtual servers) machine within your network, recording network usage parameters. Recorded data is stored in the included database for historic reports.

The easy to use web-based user interface allows to configure the devices and sensors that you want to monitor. You can create usage reports and provide coworkers and customers access to dashboards with live graphs and tables.

PRTG Network Monitor includes more than 200 sensors for all common network services (e.g. Ping, HTTP, SMTP, POP3, FTP, etc.), allowing to monitor your network systems for speed and failures. As soon as outages occur the software will alert you by sending emails, SMS, pager messages, and other notifications. Request response times and downtimes are constantly recorded in the database and you can compile performance, downtime, and SLA reports at any given time.

Now you can get free server monitoring with the 100 sensor free version, use our PRTG trial link it converts to 100 free sensors after the trial period. PRTG is a great Nagios alternative.