When you’ve got a website or a network, it really is quite wise to continue tabs on it plus fix any issues whenever they occur. The most easiest and handy method of doing it is by utilizing any server/network monitoring tool that can monitor your infrastructure for almost any problems that may occur. Several free and open origin server and network monitoring tools are present out there but locating the good ones for free is not an easy task. Blow are the some famous free network related tools handling various OS flavors
Hare are the Download links and description of these Tools
Ganglia is a scalable distributed monitoring system for high-performance computing systems such as clusters and Grids. It is based on a hierarchical design
M/Monit expand upon Monit’s capabilities to provide monitoring and management of all Monit enabled hosts from one easy to use web-interface. ..
Munin is a networked resource monitoring tool that can help analyze resource trends and “what just happened to kill our performance?” problems
Nagios provides enterprise-class Open Source monitoring of hosts, services, … Learn why organizations around the world trust Nagios to handle their IT related tasks.
Observium has grown out of a lack of easy to configure network monitoring platforms. It is intended to provide a more navigable interface.
Zabbix is an enterprise-class open source distributed monitoring solution for networks and applications.
IT Organizations use Zenoss server, network, and cloud monitoring to manage their dynamic datacenters.