This article applies as of PRTG 22

Guideline for reacting to PRTG crashing

If PRTG crashed and you cannot restart it anymore, split the approach to solve this problem into the following two parts.

Get PRTG running again

First, try to get PRTG running again. You should consider this even though you might have to accept the loss of some monitoring data. The most important thing is back to work, as soon as possible. You can also install and run a trial version. This ensures that you have at least one running instance of PRTG while troubleshooting.

Try to find the problem

Second, try to find the problem. Because this can be hard work and can easily take some days even in the case of a medium-sized issue, we strongly recommend that you accomplish the first step in advance; that is, getting PRTG working again. This approach will take away some of the pressure that you might be in when PRTG crashes.

Steps to take

The following steps will help you find the problem and to resolve corresponding issues.

Make a backup or snapshot

If PRTG crashes, make a backup or snapshot. This way, you can be sure that you have the current, crashed status of PRTG at any time for later forensic analysis. For details, refer to How do I backup all data and configuration of my PRTG installation?

Pinpoint the issue

When trying to locate the issue, consider the following points:

• When did the issue begin?
• Was the issue potentially triggered by any changes to your setup?
• Did you try to reset recent changes that might have caused the issue?
• Are there any updates to the operating system, virus scanner, etc., that have recently been installed on the system?
• Have you already restarted the PRTG core server system and probe systems? See section Service Start/Stop in both PRTG Manual: PRTG Administration Tool on PRTG Core Server Systems and PRTG Manual: PRTG Administration Tool on Remote Probe Systems.
• Have a look at the log files of PRTG. These might indicate the source of the issue.

If log files are empty

If you find nothing in the log files, run the executable file PRTG Server.exe directly with the parameter INFO (no other characters necessary).

\PRTG Network Monitor\”PRTG Server.exe” INFO

The registration information popup window must appear. This test checks if the executable can be started at all and if all necessary DLLs are available.

Adjust PRTG web server and probe settings

Sometimes rogue traffic that is sent intentionally (as an attack) or unintentionally can kill the PRTG web server. For example, very frequent requests via the PRTG API, possibly by automated scripts running in your LAN.

In this case, change the port and/or IP address for the PRTG web server and probe connections. See the PRTG Manual: PRTG Administration Tool on PRTG Core Server Systems.

Revert to an old(er) configuration

PRTG saves a daily backup of its configuration file. Try to go back to a configuration that is a few days old. For details, see How do I restore a previous configuration of PRTG from automated backup ZIPs?

Migrate your PRTG installation

Try to run PRTG on a different system. This should preferably be a bare metal system so that you can rule out any issues regarding VMware. If you have a configuration with less than 1,000 sensors, then it should run on any Windows system (Windows Server 2008 R2 or later, Windows 7 or later), even on a workstation.

Please take such a new system and follow the instructions for moving your PRTG installation to this system in How can I move (migrate) my PRTG installation to a another computer?

If PRTG runs on VMware

• First, see our Best Practice Guide: Running large installations of PRTG in a virtual environment and ensure that you configurations meets all requirements listed there.
• If you can rule out the issues listed in this article, figure out if there is a snapshot of your PRTG configuration available. Can you revert to a snapshot created before your latest setup changes?
• Can you move your virtual machine to a different host? Even a workstation installation will be sufficient.

Ask the Paessler support team

If none of the tips above help you to get PRTG back up and running, please contact the Paessler support team and send the log files of PRTG (see PRTG Manual: PRTG Administration Tool on PRTG Core Server Systems, section Logs and Info).