Why is my Synthetic ActiveGate shutting down?

[HannahM]

• Summary
• Troubleshooting
• ActiveGate and Synthetic Module mismatch
• Security software
• Chromium
• Log Messages
• Windows Machines
• What's Next

 

Summary

This article contains troubleshooting steps for when a Synthetic-enabled ActiveGate is running, but the Synthetic Engine Status is showing as shutting down, as seen in Deployment Status> ActiveGates.

Troubleshooting

ActiveGate and Synthetic Module mismatch

Check if the Synthetic and ActiveGate major versions match. In the image above, they don't. 

If the major versions differ, check this article to see why the Synthetic module failed to update. 

Security software

Antivirus, anti-malware and endpoint detection software can adversely affect Dynatrace Synthetic monitoring capabilities. The security software might block the Chromium browser or Dynatrace processes responsible for executing synthetic monitors, cause Synthetic-enabled ActiveGate installation and update failures, interfere with network communication, and impact the reliability of measurements.

If the machine has any security software installed or running

• Exclude the directories and processes listed here. 
  We recommend working with the antivirus or anti-malware software vendor to find the correct settings.
  
  • On Windows, if the complete list has already been excluded, you may need to exclude the instance that the ActiveGate uses specifically, C:\Program Files\dynatrace\synthetic\Chrome-bin\chrome.exe is the default path.
• If the exclusions don't change the behavior, try disabling/ removing the machine's security software to confirm if the issue occurs without it. 
• For Windows machines, reboot the machine.

Chromium

Old version of Chromium

On Linux machines, a common cause of this behavior is an old version of Chromium. Dynatrace supports Chromium versions, which are no more than two versions behind the latest Dynatrace-supported version for a specific ActiveGate release. Chromium can be manually updated using the instructions here.

Chromium version shows as 80.0.0000.00

If Chromium version shows as 80.0.0000.00, then the Synthetic Module can't recognise the version.

For Linux machines

1. For Ubuntu machines using snap,

   1. If possible, reboot the machine.

   2. Follow these steps to uninstall and reinstall Chromium (replace the package with the expected version from here)

      sudo snap remove chromium 
      curl --remote-name https://synthetic-packages.s3.amazonaws.com/Chromium/snap/chromium-127.0.6533.88-2923.tgz 
      tar xzf chromium-127.0.6533.88-2923.tgz 
      sudo snap ack chromium.assert 
      sudo chown -R root:root /tmp/snap-private-tmp 
      sudo snap install --devmode chromium.snap 
      sudo chown -R dtuserag:dtuserag /tmp/snap-private-tmp 

   3. Restart the vuc.service, or better still, reboot the machine

      sudo systemctl restart vuc.service 

2. If SELinux is enabled, reinstall Chromium using the permissive setting.

3. Check the vuc_browser.log for the following error

   /opt/dynatrace/synthetic/browser: symbol lookup error:

   1. undefined symbol: mpg123_param2
      If the full error contains

      /opt/dynatrace/synthetic/browser: symbol lookup error: /lib64/libopenmpt.so.0: undefined symbol: mpg123_param2

      Run the following command to get the latest update of the library "mpg123-libs" (version 1.32.0 or newer is required)

      sudo dnf install mpg123-libs

   2. undefined symbol: drmSyncobjEventfd
      If the full error contains
      

      /opt/dynatrace/synthetic/browser: symbol lookup error: /opt/dynatrace/synthetic/browser: undefined symbol: drmSyncobjEventfd​

      install libdrm-2.4.123-2.el9.x86_64 or newer
      

      sudo dnf install libdrm-2.4.123-2.el9.x86_64

   3. undefined symbol: amdgpu_cs_ctx_stable_pstate
      If the full error contains

      symbol lookup error: /lib64/libgallium-24.2.8.so: undefined symbol: amdgpu_cs_ctx_stable_pstate

      
      Install the relevant library.

      sudo dnf upgrade mesa* libdrm* -y

4. Check the vuc_browser.debug.log for the following error
   

   error while loading shared libraries​

   This means a library that Chromium depends on is not installed on the machine. 
   
   Here are a couple of examples

   2025-07-22T07:26:14,779Z DEBUG [v=5] [BM-gobbler-3] ChromeGobblerLogger: /opt/dynatrace/synthetic/browser: error while loading shared libraries: libcups.so.2: cannot open shared object file: No such file or directory
   

   2025-07-24T07:30:33,010Z DEBUG [v=5] [BM-gobbler-3] ChromeGobblerLogger: /opt/activegate/synthetic/browser: error while loading shared libraries: libdouble-conversion.so.3: cannot open shared object file: No such file or directory

   
   You'll need to search the internet for the RPM containing your Linux flavor's library. For instance, if you're missing libdouble-conversion.so.3 on a Red Hat 8 machine, you would search for 'libdouble-conversion.so.3 el8'. This will provide links to suitable download pages, like https://rpmfind.net/. You can then check the name of the RPM containing this library.
   

   In this case, the library is double-conversion-3.1.5-1.el8 from the Fedora link name, but you may need to select the link to check. This is from the RPMfind link, 
   

   

   You can then install this on your machine using

   sudo dnf install RPM_NAME​

   where RPM_NAME is the link without .rpm, so for this rpm it would be 'double-conversion-3.1.5-1.el8.x86_64'

   sudo dnf install double-conversion-3.1.5-1.el8.x86_64

For all OS

See the Security software section. It is likely that an antivirus is preventing Chromium from starting up as expected. 

Log Messages

Download the logs from the ActiveGate using the ActiveGate diagnostics feature; otherwise, you can check on the machine itself in /var/log/dynatrace/synthetic or %PROGRAMDATA%\dynatrace\synthetic\log.  

Check the vuc-status.log for DiagnosticResultsHolder and see if any modules failed to be operational. There are four to check: MULTIPROTOCOL, HTTP, HTTP_SCRIPT, and BROWSER.
Where the module start up is successful, you'll see isOperational=true, for example

2024-09-18T01:10:53,190Z [DiagnosticResultsHolder]
 browser = `DiagnosticResultsChangedEvent[moduleName=BROWSER, diagnosticCasesResult=DiagnosticCasesResult[isOperational=true, cases={BROWSER_MAIN=DiagnosticCaseDetail[isAvailable=true], BROWSER_FALLBACK=DiagnosticCaseDetail[isAvailable=true]}]]`

And where the module startup is not successful, you'll see isOperational=false, for example

2024-09-23T07:40:25,237Z [DiagnosticResultsHolder]
    browser = `DiagnosticResultsChangedEvent[moduleName=BROWSER, diagnosticCasesResult=DiagnosticCasesResult[isOperational=false, cases={BROWSER_MAIN=DiagnosticCaseDetail[isAvailable=false]}]]`

Depending on which modules were unable to start up, check the relevant logs for ERRORs and WARNINGS

1. for HTTP Monitors, vuc-http.log, vuc-http.debug.log, and additional log files with stdout/stderr output in the executors subdirectory

2. for Browser Monitors, vuc-browser.log and vuc-browser.debug.log

   1.  Running as root without --no-sandbox is not supported
      . The issue is likely related to the user running the Synthetic Engine. This should be run by dtuserag and not root. Reinstalling the ActiveGate will correct this behavior.
   2. Failed to create directory
      The issue is likely related to the location of the TEMP directory.
      For Ubuntu with snap, version 20+, the temp directory path must begin with /var/tmp, for example, TEMP=/var/tmp/syn. Also, Dynatrace requires write access to /var/tmp to install Chromium snap packages. See note in docs
   3. No usable sandbox! If you're running on Ubuntu 23.10+ or another Linux distro that has disabled unprivileged user namespaces with AppArmor
      Although this message mentions Ubuntu and AppArmor, it can be seen on any Linux distro with or without AppArmor.  This behavior is often seen when system hardening measures have been applied and are too restrictive.
      1. Verify config_user_ns and max_user_namespaces kernel settings
      2. If AppArmor is used, confirm that AppArmor settings allow the use of unprivileged namespaces

3. for NAM monitors, vuc-multi.log, vuc-multi.debug.log
   
   

Windows Machines

1. Check if the OS is supported.
   For instance, we don't support Windows 2012 (R2), and from 1.263, we found that this causes the VUC to show this shutting down status. This is due to Google stopping support for Chrome on Windows 2012 (R2) with Chrome 109. https://support.google.com/chrome/a/answer/7100626?hl=en

2. Check if any recent Windows updates have been applied, like this one, prevented Chrome from starting. 
3. Reboot the machine
4. If any antivirus or anti-malware applications are running on the ActiveGate machine, see the Security software section above. 
   
   Note: Since Chromium 129, Antivirus settings that previously allowed Chromium to be installed and run have been found to be insufficient, and the complete list from here must be excluded. 
   For the Chrome process, you may need to be very specific and exclude the instance ActiveGate uses; C:\Program Files\dynatrace\synthetic\Chrome-bin\chrome.exe is the default path.
   
   

What's Next

If none of the previous steps resolved the issue, open a chat and provide the Support Archive from the ActiveGate with the troubleshooting steps you have already completed.

You can find further troubleshooting tips for Synthetic in the Synthetic Troubleshooting Map

[ElmarS]

Dear Hannah,

We have the problem with ‘Chromium version shows as 80.0.0000.00’ again and again.
It happens about once a month on different Ubuntu ActiveGates.
Is there already a permanent solution for this available?

Best Regards,
Elmar

[HannahM]

Hi Elmar, 

thanks for the feedback. I wasn't aware of this being a regular occurrence for customers; rather more a one-off to have to reinstall Chromium. Can you create a support ticket and we'll check further on it? 

Thanks, Hannah

[Islam_Zedan]

Thank you for the Tips 👍