PRTG Manual: Failover Cluster Configuration

PRTG offers single failover clustering in all licenses—even using the freeware edition. A single failover cluster consists of two servers ("Current Master" Node and "Failover Node"), each of them running one installation of PRTG. They are connected to each other and exchange configuration and monitoring data.

Illustration of a Single Failover Cluster

Illustration of a Single Failover Cluster

For setting up a cluster you need two or more servers and there is one core installation necessary on each of them—with different settings configured for each type of node. In return, you benefit from seamless high-available monitoring with automatic failover and/or multi-location monitoring.

In a cluster, you can run:

  • 1 Master Node
    On the master node, you set up your devices and configuration. Also notifications, reporting, and many other things are handled by the master node.
  • Up to 4 Failover Nodes
    You can install one, two, three, or four additional nodes for fail-safe, gapless monitoring. Each of these nodes can monitor the devices in your network independently, collecting their own monitoring data. The data can be reviewed in a summarized way, enabling you to compare monitoring data from different nodes.

Note: During an outage of one node, you will see data gaps for the time of the outage on that node. However, data for that time span will still be available on all other cluster nodes.

Before Getting Started

Configuring a cluster with one failover node is the most common way to set up a seamless network monitoring with PRTG. You will need two servers running any Windows version (XP/2003 or later); your servers can be real hardware (recommended!) or virtual machines.

Please make sure the following:

  • Your servers must be up and running.
  • Your servers must be similar in regard to the system performance and speed (CPU, RAM memory, etc.).
  • In a cluster setup, each of the cluster nodes will individually monitor the devices added to the Cluster Probe. This means that monitoring load will increase with every cluster node. Please make sure your devices and network can handle these additional requests. Often, a larger scanning interval for your entire monitoring is a good idea. For example, you could set a scanning interval of 5 minutes in the Root Group Settings.
  • We recommend installing PRTG on dedicated real-hardware systems for best performance.
  • Please bear in mind that a server running a cluster node may in rare cases be rebooted automatically without notice (e.g. for special software updates).
  • Both servers must be visible for each other through the network.
  • Communication between the two servers must be possible in both directions. Please make sure that no software- or hardware firewall is blocking communication. All communication between nodes in the cluster is directed through one specific TCP port. You will define it during cluster setup (by default, it is TCP port 23570).
  • A Failover Master will send notifications in case the Primary Master is not connected to the cluster. In order for mails to be delivered in this case, please make sure you configure the Notification Delivery settings in a way they can be used to deliver emails from your Failover Node as well (for example, using the option to set up a secondary Simple Mail Transfer Protocol (SMTP) server).
  • Make your servers safe! From every cluster node, there is full access to all stored credentials as well as other configuration data and the monitoring results of the cluster. Also, PRTG software updates can be deployed through every node. So, please make sure you take security precautions to avoid security attacks (hackers, Trojans, etc.) You should secure every node server the same careful way as the master node server.
  • Run the nodes in your cluster either on 32-bit or 64-bit Windows versions only. Avoid using both 32-bit and 64-bit versions in the same cluster, as this configuration is not supported and may result in an unstable system. Also, ZIP compression for the cluster communication will be disabled and you may encounter higher network traffic between your cluster nodes.
  • If you run cluster nodes on Windows systems with different timezone settings and use Schedules to pause monitoring of defined sensors, schedules will apply at the local time of each node. Because of this, the overall status of a particular sensor will be shown as Paused every time the schedule matches a node's local system time. Please use the same timezone setting on each Windows with a cluster node in order to avoid this behavior.

Start Now!

Ready to get started? Please go to Failover Cluster Step by Step!


Knowledge Base: What's the Clustering Feature in PRTG?

Knowledge Base: What are the bandwidth requirements for running a PRTG Cluster?

Knowledge Base: What is a Failover Master and how does it behave?

Knowledge Base: I need help with my PRTG cluster configuration. Where do I find step-by-step instructions?

Knowledge Base: PRTG Cluster: How do I convert a (temporary) Failover Master node to be the Primary Master node?



Advanced Topics