Linux Monitoring

Howto Monitor Linux Systems

Howto Monitor Linux Systems

The secret to a smooth running system is your ability to monitor and keep track of the current state of your system. Thankfully Linux has numerous tools built in and freely available to help you. Below are some of the popular and most useful tools that every system administrator should have in his or her toolbox. Using many of the tools below, you will have the ability to monitor CPU Utilisation, cores, Load averages and runqueues. You will have the ability to identify processes and the resources that they are consuming. You will be able to monitor your network interfaces. Click on the links below to go to the relevant information page/tutorial:

Fully Automated Nagios

Fully Automated Nagios is a Linux distribution based on CentOS that comes pre-built with some of the most commonly used tools with Nagios.
FAN comprises of a CentOS Linux distribution, Nagios Core, Centreon Dashboard and Nagvis.

Nagios Monitoring Tool

Nagios is a free monitoring tool available for most Linux distributions. Nagios is a monitoring tool that can monitor local and remote servers and your network infrastructure. Nagios can also run custom scripts on remote servers. For a quick overview of Nagios and NRPE, click on the Nagios image.

nmon monitoring tool

nmon is a free monitoring tool available for most Linux distributions. nmon allows you to monitor and record important system information such as CPU, Memory, Swap, Top Processes and their associated resources, Network, NFS, Filesystems and Kernel stats. For a review of the nmon monitoring tool, click on the nmon image.

htop monitoring tool

htop is another very popular system monitoring tool available for most Linux distributions. htop is often seen as a more enhanced version of the top utility. htop provides an easy to use colour interface for monitoring your systems resources. For a review of the htop monitoring tool, click on the htop image.

iptraf monitoring tool

iptraf is a console based network statistic utility that gathers information about your TCP / UDP packets, network interfaces in real time. For an overview of iptraf, click on the iptraf image.

ntop monitoring tool

ntop is a networking tool / probe that can gather and map your network usage. Tables and graphs can be generated with ease indicating how well you network is performing. Monitor inbound and outbound traffic.

dstat monitoring tool

dstat is a versatile tool for generating real time system statistics. Monitor disk performance in conjunction with networks traffic. Dstat is often used instead of vmstat and iostat because of its extra functionality and ease of use. Export data in csv formats for use with Libre Office / OpenOffice. For a full overview of dstat, click on the image.

vmstat monitoring tool

vmstat (Virtual Memory Statistics) is a system monitoring tool that collects and summarises system statistics. Memory, processes, interrupts, paging and block I/O information can be displayed easily. Monitoring intervals can be specified so that near real time stats can be produced. For more information, click on the vmstat image.

iostat monitoring tool

iostat is a simple tool to display input and output statistics relating to storage. iostat is often used to diagnose issues with local and remote storage. For a full review of the iostat utility, click on the iostat image.

nmap monitoring tool

nmap is a system network security scanning tool which can discover hosts and services running on a network. nmap has the ability to discover hosts, their operating systems and running services. Port ranges can be specified for scanning. nmap is often used to test a systems security by identifying what network connections can be made to it. For a full overview of nmap, click on the nmap image.

top monitoring tool

top is one of the most common and frequently used command by System Administrators to get a quick system health check. An overview of CPU utilisation, Load, Memory, swap and processes are displayed by default. An overview of the top utility is covered in the process monitoring section. Click on the image for more information.