@cfoo    I see the following in the Nimbus log:   [ERROR] Error when processing event org.apache.storm.generated.KeyNotFoundException: null   Could you please try the below action plan and let us know how it goes:    - Increase the JVM of the nimbus from the existing value to keep the nimbus up for a few additional moments to kill the topologies. - stop all the topologies - delete the znode /storm ( From zk cli : rmr /storm ) - take a backup of storm.local.dir and delete the same( From zk cli : rm -rf <value of stormlocal.dir> ). You can check it in the storm.yaml file - start the supervisors and nimbus, check if the services are up and running - If there is no Nimbus service running, then the only way to remove the topology processes would be to manually kill the worker processes on all worker nodes.   If you found this response assisted with your query, please take a moment to log in and click on  KUDOS 🙂 & ”Accept as Solution" below this post.   Thank you. ... View more