The literal meaning of infrastructure is the foundation or the base of an organization. As Linux is found under a varied range from cell phones to supercomputers it is very important to monitor the infrastructure. The Linux infrastructure monitoring tools help you keep a track whether the available IT infrastructure is performing in the way it should. The tools are there to help in avoiding being taken offline and then evaluate if the resource need of the organization has outgrown the available infrastructure. Your Red Hat Certification is of great help to understand the tools better and use it judiciously. Infrastructure Tools You Need to Survive: Server Density: This is a server monitoring infrastructure tool .Due to the web interface; it allows setting alarms and also viewing graphs that are related to all the systems and network metrics. To assist you more it can also set up a thorough monitoring of websites and tell if they are up or not. You can set permissions for the users and thus extend the monitoring with api. It already supports Nagios. SysUsage: It is helpful in monitoring your system on a continuous basis mainly through Sar and also other system commands .You start getting notification once a threshold of your system is reached. It can be operated from a centralized place. A web interface is provided to view all the required statistics. KDE System Guard: It not only monitors the system, but also is a task manager Server metrics of different machines can be viewed with the help of the worksheet. It also helps to kill and start a new process if required. Munin: A network and system monitoring tool that has an interface to display the graphs created by RRD tool. It provides alerts if the metrics crosses the threshold and emphasizes on the plug. Zabbix: It uses the various databases to store the statistics of monitoring .The Core is scripted in C and the front-end is in PHP. Red Hat Certification makes you more competent to use these tools.