As market and monitoring software evolve, deciding which of all network monitoring tools implement on your business

Would you like to know which is the best network monitoring tool for you or your company? Below we’ll be making a comparison among the best tools to monitor networks that you may currently find in the market (free and paid).

Network monitoring is one of the most important aspects within the different network tools we have. To make it easy for you, we have used our experience with IT monitoring software and we have assembled those that we did not know to be able to compare them in equal conditions.

Our goal is not to show that Pandora FMS is the best network monitoring software, but to give you an objective overview so you can choose the tool that best suits your needs. Every installation is a whole different world and not all networking tools apply to all environments.

Due to the success of this article and the different questions that are coming to us regarding different network monitoring tools and recommendations to follow for your choice, we wanted to broaden the information to make it the most useful and complete article for all of you.

If so, we have something to tell you. A free monitoring program for you to try wherever you need: home, office, office, company… This software monitors everything:

When should we implement network monitoring in our organization?

To find out whether this article is for you, we want to tell you what are the conditions that must be met for you to continue reading. Clearly, if you already have a network monitoring tool in your organization and want to change it, you’ll know what I’m talking about and you can move on to the next section.

If this is your first assessment of different network monitoring tools, then you should ask yourself:

  • Does my organization’s business depend to any extent on the availability of my networks?
  • Does the number of components in my network start to get so large that it takes me a long time to manage them?
  • Is the traffic originating in my network increasing and I do not know if it is well sized and whether there are bottlenecks?

If these are questions that are on your mind, this article will help you answer them.

What are the advantages of network monitoring?

If the right tool is chosen, the main benefit of a network monitoring system is the cost reduction that comes with using it.

You will be able to optimize your installation and its components. Not only will you be able to see at a glance the global picture of your installation, but you will find out when you need more hardware and when you are oversized.

You may also detect bottlenecks in your networks and find out what is the cause and solve it, or anticipate problems and prevent them from becoming worse.

With a good monitoring tool and its correct implementation, you will be able to detect intrusive or malicious traffic.

You can also generate logs and analyze your installation’s performance over time, being able to detect problems and associate them with the modifications made to the network.

Checklist to choose the perfect network monitoring tool

We know that the process of evaluating a monitoring tool is complex and making mistakes means wasting time, money and complicating your infrastructure. At Pandora FMS we have replaced different tools by ours, because our clients had an installation that had become very expensive and complicated, due to the poor choice of software to monitor their infrastructure.

For that reason, we created this checklist with the main elements to take into account to properly evaluate any network monitoring software.

  • Make sure that the tool not only monitors networks, but that it can also scale and monitor more elements of your organization, such as applications, servers and business processes. If your choice is the right one, you will soon discover all the benefits of these types of tools and you will want to grow and monitor more of your organization’s elements.
  • Considering that you probably want to boost your organization’s monitoring by adding applications and servers that you already have installed, ask what applications are supported by the network monitoring tool. This will let you know if it will support your installation’s manufacturers.
  • Beware of the licensing system. Some tools offer multiple types of licenses and when you want to increase the number of monitored elements or the type of elements to be monitored (applications, business processes, certain servers, etc.) some companies take advantage to increase costs disproportionately. Ask about their licensing system before choosing a tool.
  • Configuring your software and managing it is very important. There are network monitoring tools that offer complex configurations not standardized at all, which makes administrators become indispensable in your organization, but then you’ll have to throw away your network monitoring system if they ever leave your company.
  • Scaling possibility to evaluate costs. In addition to scaling regarding features, as discussed above, monitoring can encompass thousands of different nodes or elements. We live in an interconnected world and many organizations need to monitor all the elements connected to their internal networks such as mobile devices, vehicles, ATMs, etc. It is in these cases that your monitoring network grows and it is vital for your tool to monitor thousands of devices with the same efficiency and performance. Ask your provider about the possibility of scaling and performance that the tool has and especially what hardware it needs.
  • There is an increasing need to integrate external elements into your monitoring system. To that end, it is very important for the tool chosen to have an API that allows other applications to be integrated.
  • Another thing to point out is the alert management system. It is very important that the tool allows you to use multiple communication channels and that you can be flexible, not only in terms of content but also in terms of sending policies.
  • If your company has virtualized systems, it is very important for your network monitoring software to also cover virtualized installation monitoring. In addition, and with the purpose of being able to increase your monitoring in the future, it is important that you can monitor not only the machines within the virtualized system, but the virtualization infrastructure itself. For containers you must take the same approach.
  • Possibility of inventorying and seeing in a simple way the components of your network and even their geolocation, if your company manages elements in different locations.
  • Embedded system monitoring is another point to consider if your organization needs to monitor hardware on devices that do not use common systems. For example, at Pandora FMS we have monitored bus fleets and we can find out the status of each bus thanks to which we monitor the hardware of its mechanics.
  • A very important feature is the reports creation and their submission. You should be aware that network monitoring status reports will most likely be requested and should be clear, exportable and suitable for all profiles in your company.
  • Another very important option is the possibility of offering monitoring with or without agents. Due to the nature of different networks or network elements, an agent may not be able to be installed at times and monitoring without agent installation at the destination to be monitored will be required.
  • Remote monitoring If you are going to monitor different networks located in different locations or with different owners, it is important that you can remotely monitor and you can monitor all these networks from the same point.
  • More and more organizations decide to migrate some or all of their infrastructure to the Cloud. If this is your case, it is very important to check that the chosen network monitoring tool will allow you to do hybrid monitoring (your own CPD and the Cloud installation) and group everything in the same dashboard.
  • Ability to save and analyze history. This is one of the features you should ask your network monitoring tool no matter what. It is very important not only to be able to find out what is happening in real time, but to be able to analyze what happened in the past and therefore be able to learn and modify the tool according to what happened over time.
  • Finally, check that the dashboard where network monitoring is presented and its results are adapted to your needs and the possible future needs that you may face when you scale your system.

You may check the features to take into account when choosing a network monitoring tool, here.

The best tools for network monitoring under examination. Useful if you are concerned about your network status and your system availability. Useful if you are concerned about your network status and your system availability.

Note: All trends discussed in this article are taken globally.

The 16 Best Network Monitoring Tools Compared

As we said at the beginning, we’re going to take a look at the network monitoring tools you can get today for you or your organization. We will give a brief description of the software and its usage trend, to analyze the advantages and disadvantages of using it.

Finally, we will talk about Pandora FMS as a comprehensive monitoring solution. A tool whose FREE DEMO of 30 days  is available if you want to use in its Enterprise version, to monitor more than 100 different devices.

1. Nagios

Nagios is probably the best known free tool. Since 1996 they have been working in the USA to build this monitoring software. The Nagios core is the most important part of the tool and plugins can be built on it to monitor particular elements.

It is interesting to see how the trend of its demand on the Internet has been decreasing over time. What was once one of the most powerful and well-known network tools is now losing ground.

Interes mundial sobre Nagios

The great use of this tool is due to the fact that it was the first player to develop a tool that covered indispensable features in network monitoring. For that reason, Nagios became a very popular solution. Thanks to this large initial market penetration, it is still one of the most used.

You may read more detailed comparisons between Nagios, Pandora FMS, Zenoss, Cacti and Zabbix at these links:

In short, Nagios was the source of monitoring and, in fact, many new network monitoring tools have inherited its code and evolved it. Although you have many profiles on the market, these must have a very technical knowledge and your installation will depend on them 100%. Any future migration may be complicated.

Is there an open version? Yes.

Nagios Pros

  • There are many profiles with Nagios experience.
  • If you have great knowledge on the tool, the manual configuration can give you a lot of power to monitor isolated and particular cases.
  • It offers many plugins to adapt Nagios to the user’s needs.
  • Its basic configuration is very easy.

Nagios Cons

  • Complex configuration and advanced editing, due to the need to make many manual modifications.
  • The graphical interface lacks good usability.
  • High learning cost.
  • Each additional installation is a “puzzle” in which more than a standard product you have your own implementation, with hundreds of patches and your own or third-party code, which make it a complicated tool to evolve or maintain.
  • Simple and straightforward reporting.
  • Very poor in its SNMP processing, both polling and trap management.

2. Zabbix

This Lithuanian company has been working at Zabbix since 2005. It is an easy-to-configure monitoring software, which has a powerful graphical interface. However, its performance starts to drop when too many nodes are monitored. The monitoring service stands out without the need to install agents.

Experience tells us that up to 10,000 nodes can be monitored without performance problems.

We show you the trend of interest in Zabbix.

Interes en la herramienta de monitorizacion Zabbix a lo largo del tiempo

We get the feeling that many Nagios users switched to Zabbix because it picked up the glove and is starting to have the visibility that Nagios had before. The problem we see is its scaling for large CPDs. You must be very careful, because if your installation has several elements of the same type (for example databases) their configurations will be complicated.

You may read more detailed comparisons between Zabbix, Pandora FMS, Zenoss, and Nagios at this link:

Comparison Zabbix vs Nagios vs Pandora FMS

Does it have an open source version?Yes. Zabbix only has a free version.

Zabbix Pros

  • Its community is quite active.
  • It is powerful at a low level.

Zabbix Cons

  • Although it has been used in large installations, from 1000 nodes onwards, its performance decreases.
  • Difficult to create and define report and alert templates. Configurations may require many clicks and steps to complete them.
  • It doesn’t have real-time reports.
  • It is difficult to debug when there are errors.
  • Poor trap processing.

3. Pandora FMS

In its free version, Pandora FMS is able to monitor more than 10,000 nodes and covers (without limitation) network, server (agent-based or remote) and application monitoring. Full features on alerts, reports, third-party integrations through API, etc.

You can USE Pandora FMS for FREE forever and for more than 10,000 nodes, would you like us to tell you how?

It is one of the few tools whose architecture does not start from Nagios, but is created from scratch, which allows it to scale perfectly in large environments. An environment with more than 100,000 nodes has been monitored without performance problems (in its Enterprise version).

We also highlight its integration with mobile devices, not only to access the console but also to monitor them thanks to their geolocation system.

Its network auto-discovery system is able to find all the elements that make up a network quickly.

The evolution of interest in Pandora Flexible Monitoring Software has remained stable over time, despite small one-off variations.

Evolucion del interes en pandora fms a lo largo del tiempo

Does it have an open source version? Yes.

Pandora FMS Pros

  • It monitors all areas (servers, applications, networks) with a single centralized console.
  • Scalability (tens of thousands of devices).
  • Network maps, reports, SLAs, integrated notifications, service maps, event correlation, log collection… and much more.
  • It is an “all-in-one”.

Pandora FMS Cons

Its user community is not as large as other applications like Zabbix or Nagios.

4. Solarwinds

Solarwinds is one of the most well-known network monitoring tools. It stands out for its automatic network and node mapping, without the need for manual actions. It has a fairly powerful graphical interface in which you can easily see the network topology and its status. Solarwinds allows integrating virtual machines into its monitoring.

It is a very good option for medium-sized companies, although they must be able to afford the price of their licenses (among the most expensive on the market).

Its trend shows that, having had overwhelming success in 2004 and 2005, it is in a state of stagnation and decline. In fact, the abrupt upturn seen in December 2020, far from being positive, is the most negative thing that has happened to the company Solarwinds Inc, since it comes from the official notice of the company in face of the famous hack that SolarWinds suffered over several months.

Solarwinds a lo largo de los anos y el efecto del hackeo de Solarwinds

Does it have an open source version?NO.

SolarWinds Pros

  • Great graphical interface.
  • Very good community behind SolarWinds.
  • Mobile access.

SolarWinds Cons

  • Configuration of manual and file alerts.
  • The reporting system must be upgraded.
  • It doesn’t integrate with Cloud apps like Amazon.
  • Not all operations can be performed from the same panel and other tools must be accessed.
  • Its license means that every once in a while you have to look at every checkup, since it is licensed based on each one of them.

5. GroundWork

This American company reuses different pieces of software from Nagios, Icinga or Cacti to create a global solution. It manages to be among the best network monitoring tools, thanks to grouping other tools.

Our experience with GroundWork has not been bad, but we think integrating its different modules is complicated. In addition, it does not have many developed plugins. For large environments it runs short. It doesn’t show an extensive history when you monitor many nodes and doesn’t support platforms like HP-UX, FreeBSD. If you don’t have a great CPD and a lot of free time to fidget your way around we recommend you to take a look at it, its approach is interesting.

Their search trend is, compared to the previous ones, residual and concentrated in the North American market.

Does it have an open source version?Yes.

GroundWork Pros

It has powerful Cloud monitoring: AWS, Azure, CLoudera, Docker, Google Cloud, NedI, NetApp, OpenStack, or VMware.

GroudWork Cons

  • Very little known.
  • Scarce user community.
  • Few plugins.

6. Zenoss

American company that has created the Zenoss software to monitor storage, networks, servers, applications and virtual servers. It stands out for its monitoring without the need to use agents. In addition, it has a “Community” version with very reduced features and a commercial version with all features.

Zenoss is interesting if you don’t want to invest too much in your monitoring software. If you have few machines and you don’t think you need to invest in support and great features, you can count on Zenoss as one of your network tools. Beware, as of version 5 a very powerful machine is required.

This is the evolution of interest in Zennos as a monitoring solution:

Interes a lo largo del tiempo de Zenoss software

You may read more detailed comparisons between Zenoss, Pandora FMS, and Nagios at the following link:

Comparison Zenoss vs Nagios vs Pandora FMS

Does it have an open source version?  Yeah, but it’s too limited.

Zenoss Pros

  • Off-road in terms of platforms. It is capable of monitoring multiple platforms.
  • It features a customizable and flexible dashboard. Very powerful.
  • Great capacity when it comes to managing events. Very powerful and flexible.

Zenoss Cons

  • Depending on the complexity of the installation and what elements you want to monitor, it can be difficult to adapt.
  • The database layer can be heavy in large environments.
  • The dashboard can be slow in certain installations and requires a great deal of knowledge for optimization.
  • It only has one Mysql and its own database underneath. It cannot be integrated with other databases.
  • Topology maps are not as powerful and clear as those of other applications.

7. Monitis

Very focused on small and medium-sized companies, Monitis comes up as a great network tool and for that reason it is featured among the best network monitoring tools.

If you are a small business, this tool may be the one you need. Of course, we recommend you to use the paid version, because the free version is very basic and will probably run short, unless you have a blog or a similar website.

This has been the evolution of online interest in the Monitis tool:

Interes en Monitis como software de monitorizacion

Does it have an open source version? NO. They offer the version, but its features are very basic.

Monitis Pros

  • It includes web transaction monitoring.
  • It allows you to monitor common Cloud application systems such as Amazon and Rackspace.
  • Great customizable and dynamic graphical interface.
  • Real-time reports.

Monitis Cons

  • Very focused on Linux and Windows.
  • Difficult to add ad-hoc monitoring.
  • There is no free version.

8. Icinga

Part of the Nagios core, from which they significantly improved the graphical interface. It integrates with multiple databases and highlights its REST API interface to integrate other applications. It is highly focused on complex networks and protocol, machine resource and server monitoring.

In 2009 a fork from Nagios was created and since then, Icinga has followed its own path. In the 2014 version, they attempted to improve its performance issues by rewriting the core code. We think it’s following the same path as Nagios. It was very well received in 2009, but after a great momentum, its demand began to gradually decrease.

Evolucion del interes en Icinga que parte del core Nagios

Does it have an open source version?  Yes.

Icinga Pros

  • Clone of Nagios, technically improved by rewriting part of its core.
  • Many of the things for Nagios are valid for Icinga too.

Icinga Cons

  • Like Nagios, most of the configuration is based on scripts/text files.
  • Like Nagios, it is difficult to integrate into more modern systems that require more dynamism (virtualization, cloud, etc.).
  • High learning curve.

9. Manage Engine / OPManager

ManageEngine belongs to Zoho Group, the giant conglomerate of Indian companies, and is one of the network monitoring tools to keep in mind. Its demand trend was slightly upward a few years ago, but has stabilized over time, as the following graph shows:

Evolucion de las busquedas de manageengine a lo largo del tiempo

What we should be aware of is its large learning curve, which may be expensive at first.

Does it have an open source version?  NO.

ManageEngine Pros

  • Easy to install.
  • Very good graphical interface.
  • It offers a very wide range of features to be covered.

ManageEngine Disadvantages

  • Complex configurations with a lot of documentation. Long learning curve.
  • Complicated user experience when browsing their screens.
  • Alarm level limited to the basic ones (warning, critical).
  • Installable on Linux and Windows.
  • It lacks inventory and event correlation.
  • Non-existent features for large environments used to working with events, deployment in large architectures, etc.

10. Observium

Cross-platform network monitoring tool (mainly focused on Linux, Unix, HP). It is a good tool, but it lacks basic features that are sometimes recommended to balance with Nagios or Cacti.

Evolucion del interes en Observium a lo largo del tiempo

Does it have an open source version?Yes.

Observium Pros

  • Observium graphics stand out for their great detail and design. Interesting to show dashboards at managerial levels.
  • Easy interface and very usable.
  • Able to monitor large installations.

Observium Cons

You will be unable to configure alerts in the free version.

11. Op5 Monitor

Op5 Monitor is one of the monitoring tools that most focuses on hardware, network traffic and service monitoring. It is also based on the Nagios core.

It has the ability to monitor multiple platforms. It also monitors Cloud systems and virtual environments. We highlight its capacity for large environments and its ability to scale in these.

From 2008 to 2010 it had an increase in demand, but then began a gradual decline. Its market remains mainly Sweden, its country of origin.

Op5 Monitor y su demanda online

Does it have an open source version?There is a free version.

Op5 Monitor Pros

  • Easy to use.
  • Very good load balancing system.

Op5 Monitor Cons

  • Difficult to extend features and monitoring on our own.
  • It does not allow deployments from the console, they have to be manual.

12. Opsview

OPs View is a tool focused on network and application monitoring. It began to be developed in 2003 and, like many other tools, started from one of the first versions of Nagios.

Here at Pandora FMS, we quite like this product, even though its demand is decreasing. Although you have to be careful with the performance of the tool.

The trend in the demand for OPsView is very similar to that of OP5, until 2012 it had a large increase, while from this year its decline was accelerated.

Demanda de OPsView

Does it have an open source version?Yes. There is a free version.

OpsView Pros

It’s a rewritten Nagios, so some of the plugins do.

OpsView Cons

  • Very rigid monitoring dashboard.
  • Limited reports and no possibility of being exported.
  • Limited plugins developed for OPSView.

13. PRTG Network Monitor

PRTG Network Monitor is a network monitoring tool that stands out for its great interface and ease of use. It has great flexibility when it comes to setting up alerts and its reporting capacity is admirable. The free version (but not open source) is limited to 100 types of applications to monitor.

PRTG is an application that only runs on Windows machines such as Microsoft Network Monitoring. In any case, we emphasize that its monitoring is multi-platform and it is also capable of monitoring virtual systems and applications in the Cloud. It allows you to display reports in real time.

Its evolution, although decreasing, has remained quite stable over the years:

PRTG Network Monitor como software de monitoreo y su evolucion en trafico

Does it have an open source version?No, it has a free version and quite reduced, but not open source.

PRTG Network Monitor Pros

  • Very good interface with great possibilities to navigate among their data.
  • Monitoring can be accessed from mobile systems.
  • Reports in PDF/HTML.
  • Very powerful and flexible alert system.

PRTG Network Monitor Cons

  • Certain plugins require additional user licenses from Microsoft, so costs skyrocket.
  • Limited scalability.
  • Not flexible when it comes to implementing your very own checks.
  • Difficult to deploy in environments with complicated connectivity.
  • Very poor for server or application monitoring.

14. Whatsup Gold

Whatsup Gold is one of the best network monitoring tools when it comes to load balancing your systems. Its scaling is horizontal and allows various processes to be used to distribute the load. You can perform some automatic actions based on the events that took place.

Like other tools, such as Pandora FMS or Solarwinds, it has a system to auto-discover networks and topologies. In addition, by creating proprietary scripts, more applications or services can be added and integrated into monitoring.

You can connect from mobile devices to access the monitoring dashboard. Alerts can be received through email, SMS and other different types and their information is offered in real time.

In spite of everything, its search trend is decreasing:

Whatsup Gold como herramienta de monitoring

Does it have an open source version?No.

Whatsup Gold Pros

  • Easy setup and network discovery process.
  • Reports.

Whatsup Gold Cons

  • Its console and navigation are not very intuitive.
  • Configuration is divided between web configurations and manual configurations per console.
  • Limited scalability.
  • Very poor for server or application monitoring.

15. OpenNMS

After the large number of requests to review this monitoring tool, we have included OpenNMS in our list of tools.

OpenNMS is a 100% open source software. All the software is free and its form of monetization is through consulting services by the company The OpenNMS Group, which are the ones that maintain the product.

As it can be seen in the graph below, the demand for OpenNMS is decreasing over time.

OpenNMS a lo largo del tiempo

Does it have an open source version? Yes.

OpenNMS Pros

  • It is a very flexible tool with lots of capacity, but one of its biggest problems is the learning curve and its graphical interface, which makes it often complex to handle.
  • It provides a good integration with alert systems such as SMS and emails.
  • As a positive point we highlight the support of the community and the project’s wiki, very well detailed.
  • Despite its free license, OpenNMS can work like different enterprise versions, but you will have to spend a lot of time on learning and configuration.

OpenNMS Cons

  • Configuration is very manual and is based on editing scripts and XMLs. As with systems like those generated by Nagios, this manual configuration can lead to complex and difficult-to-decipher installations.
  • We also highlight as a big problem the issues it generates when importing MIBs from different suppliers.
  • Their reports are not very good to be presented at CXO or management level, because their graphs are very poorly represented and their intervals are quite fixed. No real-time information can be obtained and its granularity is not less than 24 hours.
  • Finally, and as the most important negative point, OpenNMS is as its name suggests is a Network Monitoring System, and although it is good at network monitoring, the focus on this field has made it limited regarding servers and/or application monitoring. In the absence of agents, the information you can get out of systems is practically limited to what you can get through SNMP. Today that’s not enough to monitor applications or server infrastructure elements. In some installations, we did not manage to carry it out, OpenNMS has been integrated with Nagios agents, but we do not consider it a good solution.

16. Cacti

Cacti is a complete solution for network graphic generation, conceived to take advantage of the storage power and graphics feature of RRDtool applications.

It has an easy-to-use user interface, which is convenient for LAN-sized installations.

The evolution of interest in Cacti continues to keep a good basis, despite the decrease it has suffered over the years:

Evolucion del interes sobre Cacti herramienta de monitorizacion

Does it have an open source version? Yes, it only has an open source version.

Cacti Pros

  • Easy to use and install.
  • It does what it says it does and fulfills what is expected of it.

Cacti Cons

  • That’s very basic.
  • It only works to draw data graphs.
  • Other more modern tools (Grafana) are replacing it.
  • It doesn’t scale well.
  • It does not have many basic features in a monitoring environment (events, notifications, reports, SLAs, network maps, hierarchical maps, dashboards, multitenancy, etc.)


We know that there is a lot of competition and many different options of network monitoring tools. It is honestly difficult to choose the best option, but we hope that this list will provide you with the option you need.

Most of the monitoring tools we mentioned in this article are for small and medium-sized businesses. It is difficult to find tools for large companies that offer the performance they need and that support the different technologies and protocols they need. In this category we highlight two of them: Zenoss and Pandora FMS.

You should also keep in mind that this article talks about network monitoring tools and, nowadays, it is increasingly important not only to know the status of your networks and the applications that use them, but to be able to understand how a business works from the bit that runs through a network cable to the sales that are running at any given time by a company. This point is related to business activity monitoring or operational intelligence, but we will discuss that in another article.