Hi Koji,

Many thanks for your answer / help.

> I have two things in mind could be related to your situation.
> One is NIFI-4971, it's under being reviewed now. It fixes lineage
> reporting issue when 'complete path' strategy is used.
> If you are using 'complete path', I'd recommend trying 'simple path'
> to see if that's the case.

I wat not aware of that one. Thanks for the info, and the Kafka lag too.

After investigation, it looks like my pb was simpler.

I was running:

a) Nifi 1.5 on my computer

b) HDP (with Atlas + Kafka inside) in a VM (HDP sandbox), and a lot of
processes (all ?) in this VM run inside a container also. Kafka exposes the
6667 port (by default) in the container, but I didn't noticed, at first
steps, that the container DOES NOT expose the inner 6667 port outside (that
is, on the VM).

Due to (b) - AFAIU - msgs sent by Nifi were not able to reach Kafka and
then, were not able to reach Atlas.

When my non-standbox (next to come) env will be available, I will do other
Nifi/Atlas integration tests. So far, using HDP sandbox has being a pain to
use (due inner port non-exposure).

Thanks.

Regards,
Dominique



2018-04-26 17:48 GMT+02:00 Koji Kawamura <[email protected]>:

> Hi Dominique,
>
> Thank you for your interest in NiFI and Atlas integration.
> I have some experience with that, and actually written the NiFi reporting
> task.
>
> I have two things in mind could be related to your situation.
> One is NIFI-4971, it's under being reviewed now. It fixes lineage
> reporting issue when 'complete path' strategy is used.
> If you are using 'complete path', I'd recommend trying 'simple path'
> to see if that's the case.
>
> The other one is Atlas not being able to catch up fast enough to
> consume all messages from the Kafka topic.
> This happens when lots of messages are sent to the Atlas hook topic
> from NiFi, particularly seen when different files are written or
> retrieved from file system and NiFi tries to report it, as those
> entities are reported individually.
> Following command can be helpful to see how Atlas consumes messages.
> If there're lots of LAG, those messages are waiting to be consumed and
> processed by Atlas.
>
> # Sometimes Atlas consumer is not catching up and entities are not
> created even if NiFi reported as expected
> KAFKA_HOME/bin/kafka-consumer-groups.sh --bootstrap-server server:port
> --describe --group atlas
> GROUP                          TOPIC
> PARTITION  CURRENT-OFFSET  LOG-END-OFFSET  LAG             OWNER
> atlas                          ATLAS_HOOK                     0
>   24944           31897           6953
>
> Thanks,
> Koji
>
>
> On Thu, Apr 26, 2018 at 6:50 PM, Dominique De Vito <[email protected]>
> wrote:
> > Hi,
> >
> > I have defined a simple pipeline in Nifi:
> >
> > GetFile => some processor doing a dummy transformation => PublishInKafka
> >
> > ...............with Atlas integration for lineage purposes
> >
> > Versions:
> > -- Atlas 0.8.0 (Stack : HDP 2.6.4)
> > -- Nifi 1.5.0
> >
> > and I have put some (dummy) file into the input directory, and it went
> up to
> > the end of the pipeline.
> >
> > Results:
> >
> > * a "nifi_flow" entity and a "nifi_flow_path" entity were defined in
> Atlas
> > <= good
> >
> > * PROBLEM_1: the "nifi_flow_path" entity has no input, neither output.
> >
> > But I see in the Nifi logs a trace stating that Nifi has sent a
> > "ENTITY_PARTIAL_UPDATE" json to Atlas HOOK topic, with correct input and
> > output.
> >
> > So, something looks like broken in Nifi<=>Atlas link, or within Atlas.
> >
> > * PROBLEM_2 (but Atlas related): when I use the GUI, Atlas says it can't
> > found the "nifi_flow" entity while it's available through the REST api:
> >
> > 2018-04-24 05:48:14,317 ERROR - [pool-2-thread-5 -
> > 3076c14e-9bb4-44a7-8299-d56476f3ec89:] ~ graph rollback due to exception
> > AtlasBaseException:Instance nifi_flow with unique attribute
> > {qualifiedName=76d4acd9-0162-1000-257a-7393e17b3a16@mycluster5} does not
> > exist (GraphTransactionInterceptor:73)
> >
> > ============>
> >
> > So my questions:
> >
> > 1) Did anyone meet such problems ?
> >
> > 2) Does anyone have had some (good) experience integrating Nifi with
> Atlas ?
> >
> > Thanks.
> >
> > Dominique
> >
>

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