Paessler PRTG

Enjoy high availability with
PRTG availability monitoring


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    PRTG monitors
    server availability

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    PRTG monitors
    website availability

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    PRTG monitors
    network availability

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    PRTG monitors
    email availability

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    PRTG monitors 24/7.
    At a glance.

















Starting point: Between downtime and high availability


The email server is down, the telephone won't stop ringing. Everyone is calling - from the secretary all the way to the CEO. The downtime lasts for only six minutes. But the stress and short-term work loss are immense. Calculated over the course of a year and across all components, downtime often amounts to several hours.

Every administrator wants to reduce downtime. Whether server availability, website availability, or the availability of the entire network: the stabler, the better. Interruptions should be a thing of the past. That's where PRTG comes in: Our monitoring software paves the way to high availability. PRTG alerts you promptly so you can take action before crashes arise.

With PRTG, you'll keep a constant eye on your entire network.


This short video explains why availability monitoring is important


PRTG sensors for availability monitoring

 i How PRTG defines sensors

In PRTG, “sensors” are the basic monitoring elements. One sensor usually monitors one measured value in your network, e.g. the traffic of a switch port, the CPU load of a server, the free space of a disk drive. On average you need about 5-10 sensors per device or one sensor per switch port.

View video (3:26 min.)

Website availability

Website availability

Whether it be an online store, information portal, or the website of a company, institution, or association, an Internet presence should always be accessible. Every system failure comes with lost sales and customer complaints. The Ping v2 Sensor is one of the sensors that helps you to avoid these crashes. And the Cloud HTTP v2 Sensor and Cloud Ping v2 Sensor monitor the availability of your website from a number of different locations around the world.

Email availability

Email availability

In today's world, a company cannot function without email. Be sure to take advantage of our POP3 Sensor and SMTP Sensor to monitor the availability of your mail server. PRTG also comes equipped with two email round trip sensors, which you can use to monitor whether emails are delivered and how long they need to arrive at their destination.

Server availability

Server availability

Whether SQL, FTP, or a virtual server such as VMware or Hyper-V: Your servers should always be available. PRTG monitors all your hardware. The Ping v2 Sensor serves as the central interface. When interruptions occur, this sensor sends out an alarm and all the other sensors (such as those for CPU or memory) pause automatically. This means you'll receive a single, targeted message instead of being bombarded with notifications.

Bandwidth availability

Bandwidth availability

Many administrators want to know how much bandwidth they use. PRTG is the perfect tool for SLA monitoring, for you can find out if your service provider is actually delivering the amount of bandwidth that was promised! You also get access to sensors for all kinds of different technologies. For more information, see our Bandwidth Monitoring page.

Network availability

Network availability

With PRTG, you'll enjoy an overview of your entire network. PRTG monitors all systems, devices, and applications. To do so, it relies on technologies such as SNMPNetFlowWMI, and Windows Performance Counter. To the overview.


 A quick introduction to PRTG availability monitoring



99999 percent

The goal: 99.999 percent!

When it comes to the availability of your website, servers, and databases, only one figure matters: 99.999. These “five nines” are indicative of the high availability of your network. PRTG helps you target this ambitious goal. Here’s an overview of the various availability classes (figures are rounded):

Availability class 2: 99% = 87.7 hours of downtime per year
Availability class 3: 99.9% = 8.45 hours of downtime per year
Availability class 4: 99.99% = 52 minutes of downtime per year
Availability class 5: 99.999% = 5 minutes of downtime per year


Reduce costs with PRTG!

Costs associated with IT failures

Costs associated with IT failures

Costs associated with IT failures are extremely difficult to calculate. Nevertheless, there exists a whole series of studies on this topic. According to a study by Techconsult, one hour of downtime costs medium-sized companies between €20,000 and €40,000. The interviewed companies had an average of four crashes per year, with each crash lasting an average of 3.8 hours. The total costs therefore amount to €320,000 to €640,000 - for medium-sized companies with 200 to 5,000 employees. And this is a conservative estimate.

PRTG pays off

PRTG pays off

With PRTG, you’ll reduce downtime! And you’ll enjoy a significantly more reliable network. Other benefits include cost and time savings in the area of network management.

The following figures are based on a 2015 customer survey completed by more than 600 PRTG customers worldwide.


PRTG is worth it: You’ll optimize your entire IT!

The costs for a one-year PRTG license usually pay for themselves within a few weeks.


Improvement in the availability of the entire IT

PRTG improves the reliability of your network

Cost savings in the area of network management

PRTG saves network management costs

Time savings in the area of network management

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Availability monitoring: Why PRTG is the tool for you!

An all-inclusive tool

An all-in-one monitoring tool

With PRTG, you get a centralized monitoring that covers everything. A single dashboard lets you monitor your entire network, as well as all end devices. PRTG simplifies your day-to-day work, and its configuration and set-up are quick and easy.

Built-in alarm feature

Built-in alarm feature

PRTG comes with a built-in notification system. When problems arise, you’ll immediately be alerted by email or SMS, e.g. when error messages begin to appear but the overall performance of your system is still unaffected. This means you can act promptly. 

Comprehensive reporting

Comprehensive reporting

PRTG features a customizable and comprehensive reporting system. You therefore get a reliable database for your long-term planning. With PRTG, you’ll shed light on the causes and consequences of failures, and document the load of your network.

Hume Bank

Best practice: What one bank does to stay available

"PRTG lets us constantly work in accordance with the two-man rule. PRTG notifies us immediately if something is wrong in our network. Thanks to PRTG, we can use our time and resources for the things which really demand our attention."

Brad Mennen, System Administrator at Hume Bank in Australia Hume Bank uses PRTG to monitor its LANs, WANs, servers, website, applications, and much more. To the case study.


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.”

Read more reviews

“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.”

Read more reviews


High-availability cluster monitoring with PRTG

Failover Cluster

PRTG provides for high-availability monitoring. Every PRTG license allows you to set up a simple failover cluster, whereby software runs on two servers simultaneously. If one server crashes, the second PRTG server (“failover”) ensures the smooth continuation of your monitoring. You’ll therefore reduce the risk of your entire monitoring going down in the event of a hardware or network connection failure, and can bring your monitoring ever closer to the “five nines” ideal. Additional licenses will enable you to upgrade your monitoring clusters to run up to four failover nodes.


In true PRTG fashion, setting up a simple failover cluster is quick and easy. To do so, configure one PRTG server on two different computers, each with the same license key. Decide which of your PRTG servers is to be the master node in the cluster, and launch the PRTG Administration Tool on this server.

In the “Cluster” tab, click on “Create a PRTG Cluster” and follow the instructions provided. Once you have created the cluster, open the PRTG Administration Tool on the server which is to serve as the failover node. In the “Cluster” tab, click on “Join a PRTG Cluster” and follow the instructions provided. Confirm the failover node in the PRTG web interface on the master server by activating the failover in the cluster settings. Finally, add the desired devices to the cluster probe in PRTG to enable them to be monitored by both servers.

More info on the PRTG Cluster.


christian zeh 14 one forth

Practical tip: “Hey Christian, how do I achieve high availability?”

"One of the biggest advantages of network monitoring with PRTG is that PRTG alerts you before individual parts of an IT infrastructure begin to collapse. I always recommend the close monitoring of all hardware components. These include CPU load, memory, and hard disks, as well as the amount of bandwidth that is currently being used. PRTG will send a push notification to your smartphone whenever these values approach critical levels, which means you can immediately take appropriate action - before your system really does crash. Thanks to PRTG alerts, high achievability is a reality!"

Christian Zeh, Senior Systems Engineer at Paessler AG


Definitions: Network reports – the basis for network availability monitoring

Network reports are often neglected.

While many IT managers keep a close eye on their networks, they often do without software that provides for round-the-clock monitoring. A network report allows you to quickly recognize medium to long-term developments in your network. These can include a steady increase in load or minor malfunctions that occur time and again but are easily overlooked or forgotten. PRTG lets you create simple and clear reports. Many sysadmins use our network reports to convince their managers of the need for additional resources. 

Network reports: A comparison of the tools hat generate them

When it comes to network reports, there are two types of tools on the market: specialized tools that monitor and evaluate individual aspects of your network, and all-round tools that keep an eye on your entire network. PRTG belongs to the latter. PRTG displays all your data - from the hardware, applications, and cloud solutions of all the biggest manufacturers - on an easy-to-read dashboard so you can keep a constant eye on your network. If an error occurs, you’ll be notified at once. 

Network performance

PRTG monitors the availability of your network. Along with hardware, it also monitors your available bandwidth and the traffic that flows through your network. As a result, you can keep a constant eye on the performance of your network. Network security is also a major concern. While PRTG is not a security tool, you can also monitor open and closed ports and therefore recognize suspicious traffic at once. PRTG is often used as a starting point for in-depth network analyses to quickly rule out potential causes of problems.


Availability monitoring: Only for big companies?

Medium-sized companies

PRTG is often used by SMEs (small and medium-sized companies). However, sometimes a "medium-sized” company can have several hundred or even thousands of employees. Usually the IT departments of these companies are understaffed. Sysadmins have to wear many hats, one of which is to keep a constant eye on their network. When they are quickly informed of malfunctions, their jobs become a whole lot easier. PRTG is a tool that meets all your needs and expectations. And thanks to its easily-upgradeable licenses, PRTG is also an attractive option for smaller businesses. IT managers are free to define their own personal requirements and choose the license that works best for their company.

Organizations with multiple branches

Along with conventional companies, PRTG is also used by organizations such as universities, municipalities, and government agencies. These organizations often have several branches which they would like to monitor from one centralized location. At the same time, their networks are often composed of a variety of different hardware, some of which is outdated – and thus more likely to malfunction. The need to centrally monitor devices made by several different manufacturers is also an important consideration. What’s more, the network may be used for both professional and personal purposes. Network monitoring – including the monitoring of loads, response times, and more – is therefore a vital part of the equation.

Free availability monitoring 

Searching the web for “free availability monitoring?” With PRTG, you get 100 free sensors that never expire. Even important functions such as the alarm and reports feature are free of charge for as long as you use the software. What’s more, you can always upgrade PRTG in the event that your network monitoring needs evolve.


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

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


Create innovative solutions with Paessler’s partners

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

IP Fabric

Combining the broad monitoring feature set of PRTG with IP Fabric’s automated network assurance creates a new level of network visibility and reliability.

Read more


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

Read more


UVexplorer integrates tightly with PRTG to bring fast and accurate network discovery, detailed device inventory, and automatic network mapping to the PRTG platform.

Read more


quote steve coppin

“I particularly like having breakfast at home and just surveying my domain, and understanding what's working and what isn't.”

Steve Coppin, Oxford University


We asked: would you recommend PRTG?
Over 95% of our customers say yes!


Paessler AG conducted trials in over 600 IT departments worldwide to tune its network monitoring software closer to the needs of sysadmins.
The result of the survey: over 95% of the participants would recommend PRTG – or already have.


Recommend PRTG


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


Still not convinced?



More than 500,000 sysadmins love PRTG

Paessler PRTG is used by companies of all sizes. Sysadmins love PRTG because it makes their job a whole lot easier.

Still not convinced?


Monitor your entire IT infrastructure

Bandwidth, servers, virtual environments, websites, VoIP services – PRTG keeps an eye on your entire network.



Try Paessler PRTG for free

Everyone has different monitoring needs. That’s why we let you try PRTG for free. Start now with your trial.




Network Monitoring Software - Version (February 14th, 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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