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nifi detect duplicate MapCacheServer Error

New Contributor

I have configured a DistributedMapCacheClientService and a DistributedMapCacheServer which are used by the DetectDuplicate processor. But when I try to process flowfiles using the DetectDuplicate Processor I receive an error: "Detect Duplicate failed to process session due to java.nio.channels.UnresolvedAdressException". So is there any additional configuration needed? Btw, I have installed Nifi additionally on my Hortonworks Sandbox, which is running locally.

1 ACCEPTED SOLUTION

Since you are running on a standalone NiFi instance, the MapCacheServer is running locally, then you should put 'localhost' for the property 'Server Hostname' in the client service. Let me know if it helps.

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6 REPLIES 6

Hi @Alexander Flick,

Could you share the configuration of your controller services? Are the two controller services running?

New Contributor

MapCacheServer:

6226-ybbu7.png

MapCacheClientService:

6227-xw2e8.png

Both Controller Services are enabled but how can I check that they are running?

Since you are running on a standalone NiFi instance, the MapCacheServer is running locally, then you should put 'localhost' for the property 'Server Hostname' in the client service. Let me know if it helps.

New Contributor

Yes, that helped - it works 🙂 Thank you so much!

Contributor

@Pierre Villard

In the cluster mode, if we run MapCacheServer on only NCM, does that mean once NCM fails, the MapCacheServer becomes unavailable?

Is there anyway to avoid it?

Thanks.

@Alvin Ji,

This is correct with NiFi 0.x. Unless you implement your own MapCacheServer service and separate it from NiFi, I am not sure there is a solution.

With NiFi 1.x (first version to be released in coming days, RC vote in progress), this is solved with a zero-master clustering paradigm.

; ;