Today’s software applications require developers, testers, and SysAdmins to work together (DevSecOps) more seamlessly than ever before. A single line of code or poorly configured service can negatively impact your application’s performance, causing crippling slowdowns for end-users. This is where infrastructure and application monitoring comes in.
Regarding Linux server monitoring, monitoring critical performance metrics of Linux operating systems helps SysAdmins keep tabs on their database servers, mail servers, caches, web/application servers and more. Including server OS health analysis, resources usage (disk i/o, memory, swap, CPU), network checks, Firewall/Security, MySQL performance, HTTP servers (Apache, Nginx, etc.), PHP (PHP-FPM, OpCache).
Almost two years ago, I started maintaining a list of Top 100 Server Monitoring & Application Monitoring (APM) solutions. The list contains BOTH free and paid Linux Server Monitoring and APM solutions. However, a growing list of solutions offer free accounts or are entirely free and open-source. Also, see previous articles on observability.
Datadog: Modern monitoring and analytics
Datadog is an infrastructure management service ideal for IT shops that can fully leverage its automation, application programming interface (API), and data analysis capabilities. Datadog also offers many integrations (350+), dashboards, and alerts that smaller companies will find helpful. Free accounts include core collection and visualization, discussion group support, 1-day metric retention, up to 5 hosts.
Nginx Amplify: Linux Server Monitoring + PHP-FPM and MySQL Free
Nginx Amplify is currently free; however, I’ve been told that they will introduce pricing at some point. Nginx Amplify is a SaaS‑based monitoring tool for the Nginx HTTP server. With NGINX Amplify, you can monitor performance, keep track of infrastructure assets, and improve server configuration via analysis. Nginx Amplify also monitors the underlying OS, application servers (like PHP-FPM), databases (MySQL), and other components. The control panel alerts you of both performance and security-related issues. For almost two years, I’ve used it to keep tabs on Nginx and full-page caching via fastcgi_cache. Enjoy it while it’s completely free!
Netdata: Get control of your servers. Simple. Effective. Free
See what’s happening on your systems and applications, with interactive web dashboards and performance/health alarms. Out of the box, Netdata supports MySQL, Memcached, Redis, Nginx and others. There is also a wide array of integrations (modules and plugins) – free and Open Source.
Munin: free and open-source Linux server monitoring
Munin is a system monitoring, network monitoring and infrastructure monitoring software application. This is a self-hosted solution for monitoring your Linux server, network and many other applications/services. Free and open-source.
Additional free options for Linux server monitoring/APM
Last updated: April 3rd 2022
- AppDynamics – drops to a free plan after a 15-day trial.
- Cacti – free Open Source.
- Collectd – free, Open Source project.
- Goaccess.io – Open source HTTP monitoring. (Nginx, Apache, etc.)
- Grafana – scale observability with one or all pieces of the stack.
- Icinga – Open Source Monitoring.
- Influxdb – build time-series-based applications quickly and at scale.
- Monit – free, Open Source software.
- Monitorix – free, Open Source, very lightweight.
- Nagios – You can download + install Nagios core for free.
- New Relic – drops to a free plan after a 14-day trial.
- Prometheus – Free Open source. Self-hosted.
- Telegraf – open-source and collects metrics from stacks, sensors, and systems.
- Zabbix – Free Open Source. No limits or hidden costs
- More… (Post suggestions in the comments section below)
Free Monitoring Solutions will only get you so far
Server monitoring and APM are essential to establishing and maintaining infrastructure which remains performant and operational. To monitor applications at code-level depth with minimal overhead, in real-time or within minutes, you’ll need to upgrade to paid solutions. (100+ Top Server Monitoring & Application Monitoring Tools).
It’s ok to start free; however, it may be best to select and combine solutions that offer premium options that fit within your budget as traffic, infrastructure and monitoring needs grow. For example, AppDynamics, Datadog, New Relic, etc., allow you to upgrade your account or purchase premium add-on services eventually.
Published: Jun 25th 2018
Last edited: Mar 9th 2022