Published Prep Flows may fail to run with error "Couldn't instantiate org.apache.zookeeper.ClientCnxnSocketNetty"

Published: 17 Aug 2022
Last Modified Date: 13 Oct 2022


Prep flows fail when run Tableau Server with the following error found in the Flows log.:

Couldn't instantiate org.apache.zookeeper.ClientCnxnSocketNetty


  • Tableau Server 2022.1


Option 1:

Upgrade to 2022.1.7 or higher.

Option 2:
Systems running 2022.1.4

On each computer in the Tableau Server cluster:
1) Copy file netty-transport-native-epoll-4.1.68.Final.jar from C:\Program Files\Tableau\Tableau Server\packages\vizportal.20221.22.0712.0324
2) Past file into the following folders
C:\Program Files\Tableau\Tableau Server\packages\floweditor.20221.22.0712.0324
C:\Program Files\Tableau\Tableau Server\packages\flowprocessor.20221.22.0712.0324
3) Edit the following files in Notepad:
C:\Program Files\Tableau\Tableau Server\packages\floweditor.20221.22.0712.0324\floweditor.war-classpath.json
C:\Program Files\Tableau\Tableau Server\packages\flowprocessor.20221.22.0712.0324\flowprocessor.war-classpath.json
4) Insert the following line, alphabetically, in the list of files in the *.war-classpath.json files (include comma):
5) Follow Steps 1-4 for each node on the custer
6) Once the above steps have been completed, we'll want to redeploy the floweditor and flowprocessor processes by removing them from their present node(s) and enabling them on an alternative node. Easiest method is to use the TSM GUI.
NOTE: If needed, they can simply be removed, and then re-added after the next step.
7) Apply the pending changes, which will automatically restart Tableau Server, and if need be later, the processes can be moved back to the desired node (or re-added completely) with a second configuration change.
8) Confirm the netty-transport-native-epoll-4.1.68.Final.jar is now in the corresponding folder below where the process is enabled/deployed, which means the steps above were performed correctly:
C:\ProgramData\Tableau\Tableau Server\data\tabsvc\flowprocessor\0\webapps\flow-processor\WEB-INF\lib
C:\ProgramData\Tableau\Tableau Server\data\tabsvc\floweditor\0\webapps\flow-editor\WEB-INF\lib
9) Confirm that published flows can be run successfully and new flows/existing flows can be created or modified.


Follow the steps above only replace any 20221.22.0712.0324 with 20221.22.0616.1738 (difference in version numbers). For example, step 1 would use C:\Program Files\Tableau\Tableau Server\packages\vizportal.20221.22.0616.1738, and the folders for step 2 would be C:\Program Files\Tableau\Tableau Server\packages\floweditor.20221.22.0616.1738 and 
C:\Program Files\Tableau\Tableau Server\packages\flowprocessor.20221.22.0616.1738 .


This issue has been fixed in Tableau Server version 2022.1.7 and newer.  A .jar file (netty-transport-native-epoll-4.1.68.Final.jar) was not included in the Floweditor and Flowprocessor install folders.
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