# Nagios vs Zabbix vs Prometheus: The Key Differences to Know
Nagios, Zabbix, and Prometheus are infrastructure monitoring solutions that can
monitor the status of your servers, networks, cloud services, virtual machines,
and so on. In this article, we will compare their strengths and functionalities
and find out which one is more suitable for you. Before proceeding, here is a
brief overview of each product:
Nagios Core is a free and open-source application that can monitor your servers
and services and alert you when something goes wrong. It is written by Ethan
Galstad and a group of developers as a program for monitoring Linux systems, but
it can be installed on other Unix variants.
Zabbix is another open-source software designed primarily for monitoring IT
infrastructures. It was first released in 2004 and is still being actively
developed with new releases every six months.
Lastly, Prometheus is a server monitoring tool that can collect time series data
from your server and compile them into graphs. It was originally created by
SoundCloud, and it is now an open-source project hosted on GitHub.
In this article, we are going to perform a side-by-side comparison of Nagios,
Zabbix, Prometheus so you can make an informed decision on which to use in your
organization. The comparison will be based on the following criteria:
1. Functionality Overview
2. Easy installation and deployment
3. Metrics collection
4. Architecture
5. Compatible platforms
6. Scalability
7. Data visualization
8. Incident management and alerting
9. UI & UX design
10. Documentation and support
11. Pricing
## 1. Overview
| Feature | Nagios | Zabbix | Prometheus |
| -------------------------------- | ---------------- | ------------------------ | ------------------------ |
| Easy installation and deployment | ✔ | ✖ | ✔✔ |
| Metrics collection | ✔ | ✔✔ | ✔✔✔ |
| Architecture | ✔✔ | ✔✔ | ✔✔ |
| Compatible platforms | ✔ | ✔ | ✔✔ |
| Scalability | ✔ | ✔✔ | ✔✔ |
| Data visualization | ✖ | ✔✔ | ✔ |
| Incident management and alerting | ✔ | ✔✔✔ | ✔✔ |
| UI & UX design | ✔ | ✔✔ | ✔ |
| Documentation and support | ✔ | ✔✔ | ✔✔✔ |
| Free plan | ✔✔ | ✔✔ | ✔✔ |
✖ - does not support
✔ - partial support
✔✔ - full support
✔✔✔ - excellent support
## 2. Installation and deployment: Prometheus > Nagios > Zabbix
Since all three tools are open-source, you are able to self-host them on your
server.
Nagios Core offers a step-by-step
[installation guide](https://support.nagios.com/kb/article/nagios-core-installing-nagios-core-from-source-96.html)
which describes how to get started with setting it up. The installation process
takes about 10 minutes, and you also need to install and configure the Apache
server and Nagios Plugins for Nagios Core to function correctly. If you don't
want to take time to self-host, Nagios also offers a commercial product for the
enterprise called [Nagios XI](https://www.nagios.com/products/nagios-xi).
Zabbix also has an [installation guide](https://www.zabbix.com/download) on
their website which allows you to choose the Zabbix version, the OS distribution
and version, the Zabbix component, the database as well as the web server.
However, the guide does not specify how to install and set up the database and
web server, so you'll have to do it independently.
Prometheus is the easiest one to install and deploy, as it has compiled
everything together and does not require external data storage. All you have to
do is download the [latest release](https://prometheus.io/download/) from linked
web page, and execute the `prometheus` binary. And as a result, Prometheus wins
this round.
## 3. Metrics collection: Prometheus > Zabbix > Nagios
The three tools use different strategies when it comes to data collection.
First of all, Nagios requires different
[plugins](https://assets.nagios.com/downloads/nagioscore/docs/nagioscore/4/en/plugins.html)
when monitoring different services. For instance, you need NRPE to obtain data
such as CPU load, memory usage, and disk usage from the host. Once you've set up
the plugin and the host you wish to monitor, the collected data should be
accessible through the Nagios interface. However, you cannot do much
customization here; unfortunately, there is no graphical way to create
configurations. You have to place the related directives in an
[object configuration file](https://assets.nagios.com/downloads/nagioscore/docs/nagioscore/4/en/configmain.html#cfg_file).
Zabbix, on the other hand, uses
[item key](https://www.zabbix.com/documentation/current/en/manual/config/items)
format to retrieve information. For example, an item with the key name
`system.cpu.load` will gather data of the CPU load. You can customize the result
by specifying additional parameters. For example, `system.cpu.load[avg5]` will
return CPU load average for the last 5 minutes.
Lastly, Prometheus has the most powerful metrics collection functionality among
the three. It uses PromQL, Prometheus's unique and powerful query language, to
retrieve and aggregate time-series data from a multidimensional data model in
real-time. The queried data can then be displayed as a graph or table, or sent
to external systems via HTTP protocols. Therefore, Prometheus wins metrics
collection.
## 4. Architecture: tie
Nagios uses a host-agent architecture in which the Nagios server (host) is
installed on the monitoring server, and plugins (agent) are installed on the
monitored server. The agents will periodically collect data from the server and
send it to the host.
Zabbix also has a host-agent architecture. However, it is slightly more
complicated compared to Nagios, as it requires external data storage, such as
MySQL or PostgreSQL. The database should be installed on the host server.
Prometheus has the simplest architecture among the three as you can configure it
to send or receive data. The instance sending data will be the agent, and the
one receiving data will be the host.
Overall, even though these platforms have slightly different architectures, we
can't say one is better than the other.
## 5. Compatible Platforms: Prometheus > Zabbix/Nagios
Nagios is designed to run on Linux operating systems, but it can monitor Linux,
Windows and Unix operating systems with the right plugins.
Zabbix's compatible operating system is listed in the installation guide we
introduced before. One thing to note is that Zabbix can only be installed on LTS
(Long-Term-Support) versions of your system distros, if it has one.
Lastly, Prometheus can operate on Linux, macOS, and Windows.
| | Linux | macOS | Windows |
| ---------- | -------- | -------- | -------- |
| Nagios | ✔ | | |
| Zabbix | ✔ | | |
| Prometheus | ✔ | ✔ | ✔ |
As a result, Prometheus wins this round for being compatible with most operating
systems.
## 6. Scalability: Prometheus/Zabbix > Nagios
As we've mentioned before, all three tools use host-agent architecture or
similar, which means all of them can be scaled to meet demands. However, they
don't always perform well even though scaling is possible.
For instance, since Nagios requires the user to input configurations in a text
file, and Zabbix requires you to set up external databases, they are going to
require significantly more effort when it comes to scaling.
Also, Nagios still needs to catch up with the IT infrastructure today. Many
companies and organizations find themselves having to create multiple Nagios
servers for different groups of infrastructure (agent) when a single server
cannot handle the load, which introduces the downside of unable to view your
entire infrastructure in one place.
Zabbix faces similar issues. However, there is a workaround called Zabbix proxy.
The proxy will act as the middleman between the host and the agent. It will
collect and pre-process data transmitted from the agent on behalf of the Zabbix
server, hence taking the load off of the host.
As for Prometheus, there is a tool called
[Federation](https://prometheus.io/docs/prometheus/latest/federation/), which
allows one Prometheus server to retrieve data from another Prometheus server
through the `/federate` endpoint.
For this round, only Nagios loses since Zabbix and Prometheus both offer scaling
solutions that can accommodate modern IT demands.
## 7. Data visualization: Zabbix > Prometheus/Nagios
Nagios does not come with data visualization function built-in, but it can be
added using the [NagVis plugin](http://www.nagvis.org/home). The plugin allows
you to create maps for visualizing the relationships between different hosts and
services so that when a problem occurs, you will be able to tell which
components are affected.
In comparison, Zabbix comes with much better chart and dashboard creation
abilities. For example, it allows you to create custom charts by adding filters
and constraints, aggregate multiple items into one chart, or create network maps
displaying the status of your entire infrastructure.
Zabbix also allows you to create dashboards by putting multiple views together,
allowing you to keep track of your entire organization.
On the other hand, Prometheus does not have impressive visualization ability. It
only allows you to check one graph at a time using its expression browser. There
is no way to create dashboards or customize the graphs in any way.
Overall, Zabbix has the best data visualization functionality among the three.
## 8. Incident management and alerting: Zabbix > Prometheus > Nagios
Nagios is capable of pushing notifications to selected users when an incident
occurs. However, it does not provide a user interface for this purpose so you
must input the alert rules in a text file. Also, as Nagios simply executes the
predefined command when an incident occurs, it cannot guarantee delivery of the
notification.
Zabbix's alerting functionality is much easier to use in comparison. First of
all, there is a graphical interface that allows you to define notification
methods such as email, SMS, or webhook. You can also define custom scripts that
will execute when an incident occurs.
Zabbix also allows you to create threshold-based conditions that will trigger
the alert. You can also define an escalation mechanism. For instance, when an
incident occurs, you can choose to get an email first and then a text if the
issue isn't resolved within 30 minutes. Furthermore, if it remains unresolved
after an hour, you can escalate by configuring Zabbix to call the relevant
manager.
Prometheus also has an alerting mechanism similar to Zabbix. However, you need
to install the [Alertmanager](https://github.com/prometheus/alertmanager), which
is a separate package. Afterward, you'll be able to create alert rules,
notification methods, and so on. Prometheus also doesn't have a graphical
interface either when it comes to defining alerts, but its official
documentation provides a few
[notification templates](https://prometheus.io/docs/alerting/latest/notification_examples/)
to make the process a lot easier.
For this round, Zabbix has the best incident management solution overall,
Prometheus come second, and Nagios' alerting functionality needs to be updated.
[note]
☎ Want to get a call, SMS, or Slack alert when something goes wrong?
Go to
Better Uptime
and set up alerts for your application, services,
and scheduled tasks in under 2 minutes.
[/note]
## 9. UI & UX design: Zabbix > Prometheus > Nagios
As for the UI and UX design, Zabbix is the clear winner.
Nagios' interface looks outdated as it hasn't been updated for a long time. You
may navigate through its different pages using the links on the left side of the
interface, but many key features lack a graphical interface as we've mentioned
before.
Prometheus' UI design is a bit better. However, it is too simple and lacks many
key features such as a dashboard and a graphical configuration page.
Zabbix's design is better in comparison, but it is not without issues. For
example, the navigation design is a bit too complex, and the generated charts
are not interactive.
## 10. Documentation and support: Prometheus > Zabbix > Nagios
All three platforms offer great documentation and support. However, in
comparison, Prometheus has the largest community support, with 45.5k stars on
GitHub at the time of writing. Its documentation also has a better structure,
and it includes not only the basics of Prometheus but also best practices,
real-life guides, as well as a complete tutorial that walks through common use
cases.
Zabbix has the second-best documentation among the three. But even though it is
very detailed and well-written, it is missing some real-life examples that many
users would like.
Nagios' documentation is also very detailed, but it is not as easy to navigate
as the other two.
## 11. Pricing: tie
Last but not least, let's compare their prices. All three tools are open-source
and free to install on your own server, but Zabbix does charge you for their
technical support.
Nagios offers a commercial product, Nagios XI that provides additional
functionality not found in the free version such as better visualization, better
user management, and a graphical interface for adding configurations.
## The ultimate alerting setup: Better Stack + Prometheus/Zabbix
While Prometheus, Zabbix, and Nagios each have their strengths in metrics collection and monitoring, their incident management and alerting capabilities leave room for improvement. Prometheus requires external Alertmanager configuration, Zabbix's alerting can be complex to set up, and Nagios's notification system feels dated compared to modern alternatives.
If you're looking for a more intuitive alerting and incident management solution that complements your existing monitoring infrastructure, [Better Stack](https://betterstack.com/) provides a comprehensive platform that unifies uptime monitoring, on-call scheduling, and incident response without replacing your current setup.
### Better dashboards and visualizations
While Zabbix offers built-in visualizations and Prometheus relies on Grafana, Better Stack provides an intuitive alternative that makes infrastructure monitoring simpler.
Better Stack's dashboard builder lets you create visualizations without the complexity of Grafana configurations or Zabbix templates. Use the drag-and-drop query builder to quickly assemble charts, or write custom queries with SQL and PromQL. The platform automatically aggregates metrics from Prometheus exporters, Zabbix agents, and Better Stack's own collectors into unified dashboards, with ready-to-use templates and powerful customization options.
### Enhanced alerting for Prometheus and Zabbix
Better Stack integrates seamlessly with Prometheus and Zabbix, acting as a powerful alerting layer that addresses their limitations. Replace Prometheus Alertmanager or enhance Zabbix notifications with Better Stack to get unlimited phone call and SMS alerts, sophisticated on-call scheduling, and native Slack and MS Teams integrations.
### Intelligent on-call scheduling and escalations
Better Stack provides flexible on-call scheduling that surpasses what Prometheus and Zabbix offer natively. Define escalation policies that automatically route alerts based on schedules, priority, and team availability. The platform integrates with Google Calendar and Outlook, supports schedule overrides, and provides calendar exports for visibility across your organization.
When incidents occur, Better Stack automatically creates detailed incident timelines, intelligently merges related alerts to reduce noise, and facilitates team collaboration through built-in chat integrations. This eliminates the manual coordination often required when managing incidents with Prometheus or Zabbix alone.
### Comprehensive uptime monitoring
Beyond enhancing your existing monitoring tools, Better Stack provides its own uptime monitoring with checks as frequent as every 30 seconds. Monitor HTTP endpoints, APIs, SSL certificates, domain expiration, and more across multiple geographic locations. When issues are detected, you get instant notifications through your preferred channels with screenshots and error logs for faster diagnosis.
### Complete observability platform
While Prometheus excels at metrics and Zabbix provides broad monitoring capabilities, Better Stack unifies your entire observability stack. Combine uptime monitoring with log management, distributed tracing, infrastructure metrics, and error tracking in a single platform. Query logs using SQL or PromQL, visualize metrics with drag-and-drop dashboards, and track application errors with Sentry-compatible error tracking.
The eBPF-based auto-instrumentation captures telemetry from Kubernetes and Docker clusters without code changes, providing visibility that complements the metrics you're already collecting with Prometheus or Zabbix.
### AI-powered incident resolution
Better Stack includes an AI SRE that analyzes logs, metrics, and traces during incidents to suggest potential root causes. This intelligent assistance helps you resolve issues faster than manually correlating data across Prometheus dashboards and Zabbix screens. You remain in full control while the AI accelerates your debugging process.
### Status pages for customer communication
Unlike Prometheus and Zabbix, which focus solely on internal monitoring, Better Stack includes customizable status pages for customer communication. Automatically update your status page when incidents occur, send notifications to subscribers, and maintain transparency with historical uptime data, all hosted on your own domain.
### Pricing that makes sense
Better Stack offers transparent pricing with responder licenses starting at $29/month, including unlimited phone call and SMS alerts. The free tier includes 10 monitors, 1 status page, and Slack/email alerts. Since Prometheus and Zabbix are open source, adding Better Stack gives you enterprise-grade incident management at a fraction of commercial alternatives. With a 60-day money-back guarantee, you can enhance your monitoring infrastructure risk-free.
[Sign up for a free account](https://betterstack.com/users/sign-up) and start monitoring today.
## Final thoughts
Nagios, Zabbix, and Prometheus are all popular IT infrastructure monitoring
solutions. However, Nagios Core lacks many significant features present in
Zabbix and Prometheus, unless you are willing to pay for the commercial version
(Nagios XI).
Zabbix and Prometheus are both excellent platforms but have different strengths.
Prometheus is easier to set up, and it is better at data collection due to its
powerful query language (PromQL). It also has a significantly larger community
where you'll be able to get support while configuring it to meet your needs.
When it comes to data visualization, Zabbix has the clear upper hand. Unlike
Prometheus, you can create charts, maps, and dashboards without relying on
third-party services such as Grafana. Zabbix also has a better-designed user
interface, a better user management solution, and a better alerting
functionality.
It is difficult to say which one is better than the other as it depends entirely
on your needs. If you want a one-stop monitoring solution, and don't mind the
tedious installation process, you should go with Zabbix. If you want a more
robust data collection functionality, and don't mind using third-party tools
such as Grafana and Better Uptime, you should choose Prometheus instead.