In the world of open source, when it comes to monitoring, Nagios is the most preferred choice. But managing multiple Nagios screens can be a daunting task. while looking for a simple solution i came across NagCen.
NagiosCenter is a centralized viewer to show data of several (more than one) Nagios server spreaded in different networks. It uses therefore a parser in python and also an PHP Mysql Web-fronted.