What are some of the best network monitoring tools for Linux?

Hello everyone

I would like to know some of the best network monitoring tools that a System or Network Administrator can use to monitor a network.
One of the most important properties of the tools to consider should be ways of blocking certain hosts from the access point, re-connection of blocked hosts and many more.

Thanks

Good day aaronkili45 ! . Zabbix will really help in setting up a monitoring system for your network, obviously depending upon your network size. I really love it as we were able to build up an awesome monitoring system with <350 workstations/servers. Any data can be populated using zabbix templates which really helps.

http://www.tecmint.com/install-and-configure-zabbix-monitoring-on-debian-centos-rhel/

@wubyz thanks a lot let, me find more about it

How can i configure it on Ubuntu 14.04 or do i follow the same steps?