Nifi Certificate Authority - slave component is down

[#1]

Hi community,

We have a Hortonwork cluster of 2 Nifi nodes: A and B.

Nifi UI is accessible in both node A, B without any problem.

From Ambari dashboard, I got the message saying: "The following slave components are down: Nifi Certificate Authority". The message raised for node B.

I checked the nifi log on node B, there are several messages in ERROR level:

"2017-12-29 19:03:22,517 ERROR [Timer-Driven Process Thread-8] o.a.n.p.standard.HandleHttpResponse HandleHttpResponse[id=f339...ca6] Failed to respond to HTTP request for StandardFlowFileRecord[uuid=87...ceb,claim=StandardContentClaim [resourceClaim=StandardResourceClaim[id=15...15, container=default, section=251], offset=28771, length=40],offset=0,name=941...77,size=40] because FlowFile had an 'http.context.identifier' attribute of fa18...7e but could not find an HTTP Response Object for this identifier.

...

"

In our data-flow, we're using HandleHttpRequest/HandleHttpResponse process to maintain https connection to some client to exchange the data.

Does anyone know the reason why we got above error message? And does the error showed in Ambari (Nifi Certificate Authority) relate to above message?

Thank you,

Daniel

[#2]

The Ambari error message is not related to the error messages in your nifi-app.log.

The error messages about HandleHttpRequest/Response seem to indicate that HandleHttpResponse is looking in the DistributedMapCache for the response object that should have been put there by HandleHttpRequest, but for some reason it is not there.

Is it possible your DMC is reaching it's max size and evicting older entries by the time HandleHttpResponse looks in the cache?

[#3]

Thanks Bryan for the feedback.

You're right. The error I'm seeing in the log is not related to Nifi CA component. It turned out that we have never used that component so we just ignore the message.

There were a duplication in our HttpResponse component - we acknowledged the messages two times which make the exception thrown out. We're able to fix that finally.

Thanks again for your input!

Have a good day!

[#4]

Hi, 

I have the same issue, i am using the (HandleHttpRequest--> {Some Process}-->handlehttpresponse) when we invoking most of the time we getting the same error.

Could you let me know how you fixed? 

Thansk

Shakeel

[#5]

@gkp_shakeel As this is an older post, you would have a better chance of receiving a resolution by starting a new thread. This will also be an opportunity to provide details specific to your environment that could aid others in providing a more accurate answer to your question.