question Re: Can't connect to the nifi UI in Support Questions

Can't connect to the nifi UI

Koffi — Tue, 17 Mar 2020 19:17:44 GMT

Hi,

I have a hadoop environment that has 2 nifi nodes running. I am not able to connect to the nifi UI since yesterday and i try do restart one of the node without any success....

In in nifi-app.log, file seeing this as only Error level error:

2020-03-17 13:42:37,974 ERROR [main] o.a.n.c.c.node.NodeClusterCoordinator Event Reported for ***-nf02.****.ca:9091 -- Node disconnected from cluster due to org.apache.nifi.controller.UninheritableFlowException: Failed to connect node to cluster because local flow is different than cluster flow.

Could please help?

Re: Can't connect to the nifi UI

DavidR — Tue, 17 Mar 2020 21:08:13 GMT

You need to stop the nifi node that is outputing that error, copy the flow.xml.gz from the nifi/conf dir from a healthy node and start nifi again

Re: Can't connect to the nifi UI

MattWho — Tue, 24 Mar 2020 19:24:36 GMT

@Koffi

When a NiFi node attempts to connect to an existing NiFi cluster, there are three files that are checked to make sure they match exactly between the connecting node and the existing copies in the cluster. Those files are:

1. flow.xml.gz

2. users.xml (will only exist if NiFi is secured over https)
3. authorizations.xml (not to be confused with the NiFi authorizers.xml file. Will only exist if NiFi is secured over https)

The output in the nifi-app.log of the node should explain exactly what the mismatch was the first time it tried to connect to the cluster.

Hope this helps,

Matt