Paessler PRTG
How To: Free network monitoring

How to use 100 sensors to keep an eye on
critical points in your IT – at no cost







Kostenloses Monitoring mit PRTG Network Monitor

The Nuremberg-based company Paessler AG's PRTG is a professional solution for monitoring complete IT environments. From hardware and virtualized environments to data traffic and applications, PRTG monitors availability and performance. The price of the solution is based on the number of 'sensors' used – that’s what Paessler calls the individual measuring points. Every license, even the Freeware Edition, offers the complete range of functions.

Paessler offers 100 sensors in the Freeware Edition.

Implemented as a comprehensive monitoring solution, this 100-sensor edition is sufficient for a small company network or large home network. However, it can also be an interesting option for monitoring critical points in a larger network.


Examples of usage for the Freeware Edition


Syslog/Trap manager

In this first example, the Freeware Edition is used as Syslog and SNMP trap receiver. Syslogs and SNMP traps deliver a lot of information to devices in the form of text messages, which are delivered to a corresponding receiver.

A single Syslog Receiver or SNMP Trap Receiver Sensor can theoretically be used to monitor an entire network: Under lab conditions (one single sensor without filters), PRTG could handle 10,000 messages per second (Syslog or trap) on a quad core desktop machine, so the software offers more than enough power reserves.

The messages are collected and can be filtered and sorted, then serve as a basis for alerts, notifications and reports. You’re left with 99 sensors that can be used as Syslog and SNMP trap receivers for individual, important devices or for other purposes entirely.



Website monitoring

A website is a company's business card, showcase and retail outlet. However, if just entering a shop takes too long, most customers won’t even come in. Constant, comprehensive monitoring is necessary in order to guarantee fast response times and general availability of a website.

With 100 sensors, the free edition offers enough options for comprehensive monitoring of one or more websites. For example, the HTTP v2 sensor can be used to monitor general availability, while the HTTP Full Web Page sensor measures the time needed to load an entire page. One can monitor specific website content for changes, or use the HTTP Transaction sensor to monitor processes like logins or filling out and sending forms.

Because the Freeware Edition also includes remote probes, these can be distributed worldwide to monitor the availability and reaction time of websites from other countries. Website operators can ensure that their sites are available for international customers as well. In addition, some sensors can be used to monitor the web server or backup processes, for example.


Secure email traffic

Email is still the main means of communication in most companies. Any disturbances in email traffic can have grave consequences. Consistent monitoring sends alerts before interruptions or failures occur and cause severe damage.

PRTG offers numerous predefined sensors for securing email traffic, including the Email Round Trip Sensors, which monitor the entire sending and receiving cycle of an email. In addition, dedicated Exchange, IMAP, POP or SMTP sensors can be used to monitor single key components efficiently and thoroughly.


Database monitoring

Databases are another critical point in many companies. Whether internal systems or websites, the performance of many processes is directly dependent on the performance of the underlying database.

The Freeware Edition offers predefined SQL sensors (MySQL, Microsoft SQL, ADO SQL and Oracle SQL) for in-depth SQL database monitoring. To this end, one sensor monitors various standard parameters, while still permitting custom SQL queries, so that the monitoring can easily be adjusted to fit individual requirements.


Printer monitoring

Printers are generally not as integral to a company as databases, email or websites, but broken printers, empty toner or print jams often make for annoyed users. Up to 50 printers can be monitored with the Freeware Edition, if two sensors are used per printer:

  • One sensor that monitors the toner levels, queue, paper, etc.
  • A second sensor that monitors statistic values, like printed pages

With the PRTG Maps feature – which involves easy-to-create HTML pages – printers can be displayed on a blueprint of the office, so the administrator immediately knows where the printer needing maintenance is located. The internal ticketing system can be used to create tickets and assign them directly to the responsible colleague.

In addition, the Freeware Edition can be used as a free and powerful alternative for some scenarios that, at first glance, seem to require expensive special solutions.


Flow monitoring

Functions that are usually available for purchase as add-ons for other standard monitoring solutions are included in PRTG.

The Freeware Edition can be used in a small scope to monitor routers and switches using flow protocol. A flow sensor (PRTG supports NetFlow, sFlow, jFlow and IPFIX) processes a flow stream from a router or switch. In this way, the free PRTG edition can monitor up to 100 flow-capable devices for free and analyzes the traffic that runs on these devices.

PRTG does not aim to replace highly specialized flow solutions with its flow sensors, but helps administrators to maintain a quick overview of top talkers, top protocols and top connections in day-to-day work.


VMware host monitoring

Like flow monitoring, monitoring VMware environments usually requires expensive special solutions or add-ons. And, like flow sensors, VMware sensors are included in PRTG's range of functions.

The Freeware Edition can be used to augment VMware's integrated monitoring with an alarm and reporting tool.

Over dedicated VMware host sensors, PRTG can read out and process comprehensive performance data. In addition, PRTG can also monitor the hardware on which the VMware host operates.


And many more...

PRTG offers more than 250 predefined sensor types, which open up a whole realm of further usage scenarios for the Freeware Edition.

These can be used to monitor firewalls, storage solutions, Active Directory or virus scanners and much more. The FritzBox sensor is an especially interesting option for home users or small companies.


Get started today with free PRTG monitoring and a quick and easy overview of all your servers.

Set up PRTG in minutes and use it on almost any mobile device.


PRTG comes with all the features you need, plus more your IT infrastructure won't want to live without.



PRTG monitors these vendors and applications in one view!


vendors vm ware



Trusted by 500,000 users and recognized
by industry analysts as a leader

“Fantastic network and infrastructure monitoring solution that is easy to deploy and easier still to use. Simply the best available.”

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“Software is absolutely perfect, Support is superior. Meets all needs and requirements, this is a must have solution if you are needing any form of monitoring.”

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“The tool excels at its primary focus of being a unified infrastructure management and network monitoring service.”

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Create innovative solutions with Paessler’s partners

Partnering with innovative vendors, Paessler unleashes synergies to create
new and additional benefits for joined customers.


By integrating PRTG with Martello iQ, you can add a fast analytics layer to improve uptime, visualize your IT environment, and integrate all of your IT systems into a single pane of glass.

Read more


Paessler and Plixer provide a complete solution adding flow and metadata analysis to a powerful network monitoring tool.

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Siemon and Paessler bring together intelligent building technology and advanced monitoring and make your vision of intelligent buildings and data centers become reality.

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“Easy to implement and configure with good technical support.”

R. v. S., ICT Manager at Heinen & Hopman Eng BV


PRTG the multi-tool

PRTG: The multi-tool for sysadmins

Adapt PRTG individually and dynamically to your needs and rely on a strong API:

  • HTTP API: Access monitoring data and manipulate monitoring objects via HTTP requests
  • Custom sensors: Create your own PRTG sensors for customized monitoring
  • Custom notifications: Create your own notifications and send action triggers to external systems
  • REST Custom sensor: Monitor almost everything that provides data in XML or JSON format


PRTG makes your job easier

Our monitoring software frees you to focus on other tasks by promptly notifying you of potential issues.


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Save effort

PRTG gives you one central monitoring tool for your servers and entire network. Enjoy a quick overview of your whole infrastructure via our dashboard and app.

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Save time

Getting started with PRTG is a breeze. Setting up or switching from another network monitoring tool is easy thanks to the auto-discovery and pre-configured device templates.

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Save money

80% of our customers report substantial cost savings with network monitoring. Your costs of licenses will likely pay for themselves within weeks.




Network Monitoring Software - Version (May 2nd, 2024)


Download for Windows and cloud-based version PRTG Hosted Monitor available


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Up to 100 sensors for free (Price List)

Unified Monitoring

Network devices, bandwidth, servers, applications, virtual environments, remote systems, IoT, and more

Supported Vendors & Applications

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