Jens,

So that would tell us that the hostname or the port is wrong, or that NiFi is 
not running/listening for load balanced connections. I would recommend the 
following:

- Check nifi.properties on all nodes to make sure that the 
nifi.cluster.load.balance.host property is set to the node’s hostname.
- You could try deleting the state/ directory on the nodes and restarting. 
Perhaps somehow it’s got an old value cached and is trying to communicate with 
the wrong port?

Thanks
-Mark


> On May 19, 2022, at 7:42 AM, Jens M. Kofoed <[email protected]> wrote:
> 
> Hi
> 
> I have a 3 node test cluster running v. 1.16.1. Which has been working fine, 
> with no errors. But i doesn't do much, since it is my test cluster.
> But now I am struggling with load balance connection refuse between nodes.
> Both node 2 and 3 are refusing load balancing connections, even after 
> stopping the cluster. I have deleted all files at node 2 and 3, but they 
> still refuse connection.
> I have not made any change to the configuration, but I have created a new 
> flow which got node 1 to die.
> The new flow is using an ExecuteStreamCommand using stdin/stdout to a shell 
> command to manipulate with some data (1 GB files). I set the "Concurrent 
> Tasks" to high so node 1 ran out of memory and stopped. It continues to stop 
> if I tried to start it again. So I deleted the flow.gz file and the run, 
> state and work folders and started the node. Now node 1 was running again. 
> But after this node 2 and 3 are refusing load balancing connections.
> I can't see what this flow have to do with this, but I have now tried to 
> remove all files at node 2 and 3 to get clean nodes. But they still doesn't 
> work
> 
> Does any one have an idea how to debug further?
> 
> From the log:
> 2022-05-19 13:22:46,268 ERROR [Load-Balanced Client Thread-2] 
> o.a.n.c.q.c.c.a.n.NioAsyncLoadBalanceClient Unable to connect to 
> nifi-n03:8443 for load balancing
> java.net.ConnectException: Connection refused
>         at sun.nio.ch.Net.connect0(Native Method)
>         at sun.nio.ch.Net.connect(Net.java:482)
>         at sun.nio.ch.Net.connect(Net.java:474)
>         at sun.nio.ch.SocketChannelImpl.connect(SocketChannelImpl.java:647)
>         at sun.nio.ch.SocketAdaptor.connect(SocketAdaptor.java:107)
>         at sun.nio.ch.SocketAdaptor.connect(SocketAdaptor.java:92)
>         at 
> org.apache.nifi.controller.queue.clustered.client.async.nio.NioAsyncLoadBalanceClient.createChannel(NioAsyncLoadBalanceClient.java:497)
>         at 
> org.apache.nifi.controller.queue.clustered.client.async.nio.NioAsyncLoadBalanceClient.establishConnection(NioAsyncLoadBalanceClient.java:440)
>         at 
> org.apache.nifi.controller.queue.clustered.client.async.nio.NioAsyncLoadBalanceClient.communicate(NioAsyncLoadBalanceClient.java:234)
>         at 
> org.apache.nifi.controller.queue.clustered.client.async.nio.NioAsyncLoadBalanceClientTask.run(NioAsyncLoadBalanceClientTask.java:81)
>         at org.apache.nifi.engine.FlowEngine$2.run(FlowEngine.java:110)
>         at 
> java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
>         at java.util.concurrent.FutureTask.run(FutureTask.java:266)
>         at 
> java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180)
>         at 
> java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293)
>         at 
> java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
>         at 
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
>         at java.lang.Thread.run(Thread.java:748)
> 
>  kind regards
> Jens

Reply via email to