NiFi: Failed to connect node to cluster because local flow is different than cluster flow

Question

After rebooting the server, NiFi does not start. Before the server reboot, I was able to shutdown/start NiFi without any issues.

I ensured that the 3 config files (flow.xml.gz, authorizations.xml, and users.xml) are identical on all the nodes.

2019-12-08 14:36:10,085 ERROR [main] o.a.nifi.controller.StandardFlowService Failed to load flow from cluster due to: org.apache.nifi.controller.UninheritableFlowException: Failed to connect node to cluster because local flow is different than cluster flow.
org.apache.nifi.controller.UninheritableFlowException: Failed to connect node to cluster because local flow is different than cluster flow.
    at org.apache.nifi.controller.StandardFlowService.loadFromConnectionResponse(StandardFlowService.java:1026)
    at org.apache.nifi.controller.StandardFlowService.load(StandardFlowService.java:539)
    at org.apache.nifi.web.server.JettyServer.start(JettyServer.java:1009)
    at org.apache.nifi.NiFi.<init>(NiFi.java:158)
    at org.apache.nifi.NiFi.<init>(NiFi.java:72)
    at org.apache.nifi.NiFi.main(NiFi.java:297)
Caused by: org.apache.nifi.controller.UninheritableFlowException: Proposed Authorizer is not inheritable by the flow controller because of Authorizer differences: Proposed Authorizations do not match current Authorizations: Proposed fingerprint is not inheritable because the current access policies is not empty.

Also, ruled out any zookeeper corruption issue by deleting the znode for NiFi in the zookeeper cluster.

I am on NiFi 1.9.1

Any help is highly appreciated.

Answer 1

This means there is a difference in authorizations.xml or users.xml, most likely authorizations.xml. I would try copying those two files from one of the other nodes over to the node that is having the problem, this will ensure they are exactly the same.

Answer 2

A suggestion, if there is case we can't copy flow.xml.gz (like it was with me) for various process restrictions. We can stop Nifi service on problematic node, rename existing flow.xml.gz to a backup (just to be sure we don't loose it) and restart Nifi service.

Nifi would automatically generate a flow.xml.gz and connect the node to the cluster. It worked for me, hence, sharing.

Thanks