3 of the Best System Monitor Tools for Ubuntu

System Monitor Htop Ubuntu Featured

As the number of devices, servers, and services you have in your business or organization grows, so does the need to monitor your systems. System monitoring, whether on premise or in the cloud, covers the capacity, activity, and health of the hosts and apps. The process is designed to cover all computing resources to root out and tackle problems in real-time before they occur.

If you’re using Ubuntu, system monitoring tools will help you spot any service failures or errors before they impact users.

The most basic tool at your disposal is the System Monitor, a built-in utility for Linux that acts like Windows’ Task Manager and offers basic activity monitoring information from running processes to what consumes the most resources.

However, you can get sophisticated system monitoring tools that show you more resource utilization information for memory, CPU, disk, and network connections.

Here are three you can use with Ubuntu.

1. Nagios


This system monitoring tool for Ubuntu offers complete monitoring of servers and workstations – including service and process state, operating system metrics, and file system usage, plus more.

It is powerful, scalable, reliable, and customizable software, despite being complex to configure. As an enduring standard in system and network monitoring, Nagios offers immense benefits such as fast detection of protocol failures and network outages, plus increased availability of services, server, and applications.

Two solutions are available for system monitoring: Nagios Core and Nagios XI.

Nagios Core


This is the open-source free version that monitors servers, applications, and services, with features such as a basic user interface with network map, reporting by SMS and email, and basic reports.

Nagios Core monitors your critical IT infrastructure components from system metrics, servers, applications, services, and network protocols. It then sends you alerts via SMS, email, or custom script when critical components fail and recover, so your admins are always notified of important events.

Reports are available providing a historical record of events, outages, notifications and alert responses for your review later plus advanced graphs to plan for upgrades before outdated systems catch you offguard.

It is a powerful open-source option for Ubuntu system monitoring with great features like a web interface, multi-tenant capabilities, and extendable architecture through integration with in-house or third-party apps, and other community-developed add-ons.

While it may have a learning curve to begin with, an active community is available if you need assistance.

Nagios XI


This is the commercial variant of the tool that has a richer range of features and automated configuration assistance.

Among its powerful features (over and above what Core offers) include the powerful Nagios Core 4 monitoring engine that gives you the highest degree of server performance monitoring.

Also included are configuration wizards to guide users through monitoring of devices, services and applications, and a configuration snapshot to save recent configurations and revert to them when you want.

You can customize your design, layout, and preferences on a per-user basis using the updated GUI, so your customers and teams get the flexibility they want. It also offers custom role assignment that ensures a secure environment.

What we like about Nagios

  • Easy to use
  • Offers free and premium (with 60-day trial) options
  • Comprehensive IT infrastructure monitoring as all mission-critical infrastructure components are monitored.
  • Allows multiple users to access the web interface and view the relevant infrastructure status
  • Fast configuration in a few simple clicks
  • Easy to set up and manage user accounts
  • Extendable architecture using add-ons

2. Glances


This is a cross-platform, data-center monitoring tool that runs on GNU/Linux, macOS, Windows, and BSD operating systems. It is written in Python language using the psutil library from where it draws information from the system, giving you as much as you need at a glance.

You can use Glance to monitor load average, CPU, memory, disk I/O, network interfaces, mounted devices, file system space utilization, plus all active and top processes.

One of its main features is the ability to set thresholds in a configuration file with four options displayed in different colors that indicate the logjam in the system: OK (green), careful (blue), warning (violet), and critical (red).

The threshold levels are set at 50, 70, and 90 for careful, warning, and critical levels respectively. You can customize these using the “glances.conf” file found in the “/etc/glances/” directory.


View critical information such as the average CPU load, disk I/O read/write speeds, current disk usage for mounted devices, and top processes together with their CPU/memory usage.

The downside with having all this information is that Glances tends to use a significant amount of CPU resources.

If you need help with Glances, there are wikis available on their website. You can also contact other developers and users on Twitter, Chat for developers, and user groups.

What we like about Glances

  • Easy to install as it is available on Ubuntu’s repository
  • Displays more information compared to other monitoring tools
  • Web-based GUI makes monitoring flexible
  • Can monitor remote systems

3. htop


htop is an interactive process reviewer and text-mode application that performs system monitoring in real-time. It offers a complete view of processes that are running and their usage. This way you can free your system from any malfunctions as it serves its purpose.

The tool is based on “ncurses” and offers support for mouse operation. Like other tools, htop uses color to give visual indications of the memory, processor, and swap usage.

A flexible, clean, and easy-to-configure summary section displayed in two columns lets you view information about your system. However, some information like CPU percentages by idle, user, or system time, may not be available.

Function keys are available to configure the summary section and add data display lists to either column. There’s also a process section that sorts factors such as memory/CPU usage, PID, or user.

Note: htop is now cross-platform since version 2.0, supporting Linux, BSD, and macOS.

What we like about htop

  • Clean and easy-to-read summary section
  • Each user has a configuration file
  • Automatic save for any changes stored in configuration files

Which system monitoring tool do you use for Ubuntu? Comment below.

Image Credits: Glances Github, Nagios, Hisham

Elsie Biage
Elsie Biage

My passion has always been to share every bit of useful information I find on tech, with the ultimate goal of helping people solve a problem.

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