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What do I have to consider when I want to do a regular cleanup of my PRTG environment?



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I prepared my IT infrastructure and set up the devices and sensors that I need for monitoring my network with PRTG. Now I also want to do regular maintenance work and cleanups of my PRTG environment, if necessary. What aspects do I have to consider?

maintenance prtg prtg-cleanup prtg-housekeeping

Created on Sep 30, 2021 7:58:47 AM by  Maike Guba [Paessler Support]

Last change on Oct 4, 2021 7:47:58 AM by  Maike Guba [Paessler Support]

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This article applies as of PRTG 21

Taking care of your PRTG environment

We recommend that you regularly review your setup of PRTG to keep your PRTG installation up to date and to make sure that you have the best possible monitoring configuration for your infrastructure. Here you can find some tips what to check in your PRTG installation and, if necessary, how to do some cleanup work.

General issues

  • Check if you still have your license document. If not, contact the Paessler customer service team to request you license from Paessler again.
  • Check if the customer contact details that you gave to Paessler, including the VAT identification number, are still valid. If you need to update your data, contact the Paessler customer service team.
  • If you use your own SSL certficate, not the default SSL certificate that PRTG comes with, check if your certificate is still valid.
  • Regularly check the Paessler Blog or subscribe to our newsletter to stay up to date on PRTG and other content related to IT, IoT, and IIoT.

License information

  • Check if your license is still up to date. You can view the license status of PRTG Network Monitor in the PRTG web interface under Setup | License Information.
    Note: For PRTG Hosted Monitor, log in to the PRTG Hosted Monitor web portal and manage your subscription there.
  • For a quick overview of your license status, go to the Welcome page in the PRTG web interface. There you can see how many maintenance days you have left and the number of sensors that is still available to you.
    Note: For technical reasons, the number of available sensors that PRTG displays here also considers your sensors in the Paused status, although sensors in the Paused status are not included in the maximum number of sensors that your license allows. To know exactly how many sensors are still available to you, add the number of your sensors that are in the Paused status to the displayed number of available sensors.

Software version and server information

  • Make sure that you run the most recent version of PRTG. You can view your PRTG version in the PRTG web interface under Setup | PRTG Status, section Software Version and Server Information.
    The version number has the following parts: year.quarter.version.build. For example, if your PRTG version is, you have installed PRTG version 72, build 1112, that Paessler released in the 3rd quarter of the year 2021.
  • Check that the selected release channel is still the channel that fits your monitoring requirements. You can view the release channel that you use under Setup | Auto-Update | Status in the PRTG web interface.
    The available channels are Stable (this is the most conservative release channel), Preview (this release channel is thoroughly tested), and Canary (this release channel is for testing purposes only). To select a different release channel, click Select Other Release Channel.

Note: You can also find your installed PRTG version including the release channel in the footer of the PRTG web interface.

System and performance

Overall system status

Check your overall system status in the PRTG web interface under Setup | PRTG Status.

Software Version and Server InformationCheck your Server CPU Load. This value should be lower than 50%.

Note: For information on how to improve your system performance, see How can I speed up PRTG—especially for large installations?.
System Startup LogCheck if the log entries of your last system startup are OK all in all.
Note: For further log files and where to find them, see the PRTG Manual: Data Storage.

Check when the last system restart took place. If it has been more than one month, we recommend that you restart your server. Optionally, you can combine the restart with the installation of the latest Windows updates.
Note: To schedule an automatic probe restart, for example, for the local probe or a remote probe, go to the respective probe's Settings tab, section Scheduled Restart Settings, and select one of the Restart Options.
System WarningsCheck that your system warnings say None.

System warnings that PRTG might show are:
- The available diskspace is too low!
- The available memory is too low!
- Connection to database lost!
- No configuration file found, but monitoring data for an unknown configuration exists!
- This beta version has expired
- The path to PRTG's configuration file (%s) could not be found. Please check network paths if applicable.
- Internal error. Restart of PRTG required.
- The license of this cluster member is not valid for operating in the configured cluster.
Sensors Sorted By Impact On System PerformanceCheck how many sensors have a High or Very high performance impact.

Ask yourself if you can exchange some of the sensors with a higher performance impact with sensors that have a lower impact on performance.

Note: For an overview list of sensors sorted by performance impact, see the PRTG Manual: List of Sensors by Performance Impact.
Sensors Sorted by IntervalCheck how many sensors have a scanning interval that is shorter than 300 seconds.

Ask yourself if the defined scanning intervals really make sense regarding the performance impact of the respective sensors on your system.
Shorter scanning intervals usually do not give you more accuracy but cause unnecessary load on your system and the network. For example, is it really necessary to search for Windows updates more often than once every 24 hours?

Tip: Change the scanning interval in the root group settings and use the inheritance mechanism of PRTG to set this scanning interval for all objects that are underneath in the object hierarchy.
System SettingsCheck if your PRTG web server ports are still correct.

If your PRTG core server system is reachable via the internet, we recommend that you only use port 443 (HTTPS). To change the PRTG web server settings, go to section PRTG Web Server under Setup | System Administration | User Interface in the PRTG web interface and select a TCP Port for PRTG Web Server.
Web Server ActivityCheck the Slow Request Ratio. This value should be lower than 10%.

Background Tasks

  • Check if there are any scheduled auto-discoveries that you do not need anymore. You can find an overview of scheduled or running auto-discovery processes under Logs | System Events | Auto-Discovery Related in the PRTG web interface.
  • Check if the similar sensors detection is enabled. This process runs with low priority in the background. If you do not need the similar sensors detection, go to Setup | System Administration | Monitoring, section Similar Sensors Detection, in the PRTG web interface and select Disable detection of similar sensors.
  • Check if the recommended sensors detection is enabled. This process runs with low priority in the background when you add a new device, when PRTG executed the last recommended sensors detection more than 30 days ago, or when you manually start the recommended sensors detection. If you do not need the recommended sensors detection, go to Setup | System Administration | Monitoring, section Recommended Sensors Detection, in the PRTG web interface and select Disable sensor recommendation.

Libraries, Sensors, and Channels

  • Check if all your libraries are up to date. Remove all libraries that you do not need, including the default libraries.
  • Check if there are any sensors that are still monitoring your network although you do not need them for your infrastructure, particularly if they have a high impact on system performance. This includes, for example, Sensor Factory, Packet Sniffer, VMware, Email Round Trip, SQL Server, CloudWatch, QoS, File, Folder, HTTP Full Web Page, WMI,and custom EXE sensors. Set the sensors to the Paused status if you do not want to completely delete them from your PRTG configuration.
  • Check the List of Available Sensor Types and the List of New Sensors in the PRTG Manual. Are there any new sensors that you do not know yet?
  • Check the number of channels per sensor. Sensors with more than 50 channels can have a high impact on system performance.

User Accounts

  • Check if your user accounts and user groups are still up to date. Update user contact details like the email address or the phone number if necessary, or disable users that do not work with the respective installation of PRTG anymore. Always keep in mind that multiple user accounts and user groups can slow down the performance of the PRTG web server.
  • Check your user access and group access rights settings.


  • Check if the maps that you created are still in use or if you can delete them.
  • Check if there are any broken links in the maps that might need correction.
  • Check if you can still retrieve embedded HTML objects and frames.


  • Check if the contact details, for example, email addresses or phone numbers, in your notification contacts are still up to date.
  • Check if there are any new default notification templates that might be of use for your specific setup.
  • Check if custom notification templates are still in use by clicking the Used by icon under Setup | Account Settings | Notification Templates in the PRTG web interface.
  • Check if your notification templates still work by clicking the Send test notification icon under Setup | Account Settings | Notification Templates in the PRTG web interface.
  • Check if there are any error messages that are related to notifications under Logs | System Events | Notification Related.

Data storage and backup

  • Check for how many days PRTG keeps different kinds of data and if you might be able to optimize your settings so that the file that contains this data does not get too large. You can change the settings in the PRTG web interface under Setup | System Administration | Core & Probes, section Historic Data Purging.
  • Manually check the \Configuration_Auto-Backups subfolder of the PRTG data directory. Does PRTG still write backups? Do these backups perhaps fill up available disk space?
    Note: For more information, see also How do I back up all data and configuration of my PRTG installation?.


Created on Sep 30, 2021 8:36:46 AM by  Maike Guba [Paessler Support]

Last change on Oct 4, 2021 7:31:22 AM by  Maike Guba [Paessler Support]

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Disclaimer: The information in the Paessler Knowledge Base comes without warranty of any kind. Use at your own risk. Before applying any instructions please exercise proper system administrator housekeeping. You must make sure that a proper backup of all your data is available.