question Re: Error importing flows from a registry instance to a fresh nifi instance in Support Questions

Error importing flows from a registry instance to a fresh nifi instance

alan18080 — Wed, 22 May 2024 16:10:56 GMT

We save some flows into a registry with postgresql and now we want to transfer to a fresh nifi instance but we are getting this error:

The Flow Registry with ID ? reports that no Flow exists with Bucket ?, Flow

Any suggestion what is it happening?

Re: Error importing flows from a registry instance to a fresh nifi instance

DianaTorres — Wed, 22 May 2024 21:42:40 GMT

@alan18080 Welcome to the Cloudera Community!

To help you get the best possible solution, I have tagged our NiFi expert @steven-matison who may be able to assist you further.

Please keep us updated on your post, and we hope you find a satisfactory solution to your query.

Re: Error importing flows from a registry instance to a fresh nifi instance

steven-matison — Thu, 23 May 2024 11:33:38 GMT

@alan18080 It seems this may be related to Process Group within a Process Group ( a known bug), but its hard to know based only on this error. You may find more verbose information in the nifi log which will help better resolve.

Here is one solution for the same:

https://community.cloudera.com/t5/Support-Questions/quot-No-Flow-Exists-quot-When-Importing-Process-Groups-with/m-p/241006

Re: Error importing flows from a registry instance to a fresh nifi instance

MattWho — Thu, 23 May 2024 11:39:47 GMT

@alan18080

Please provide more details around the steps you are performing and the exact versions of Apache NiFi and Apache NiFi-Registry you are using.

So you have an existing NiFi-Registry configured to use Postgres as its metadata database. You have already version controlled some NiFi process group(s) to buckets within this registry. And now you are trying to export those version controlled process groups from this NiFi-Registry and import into another NiFi-Registry?

What version are the two NiFi-Registries?
What steps did you perform that eventually resulted in the exception encountered? I am not clear on what you are doing when you say "transfer".
Sharing the complete error and stack trace can also be helpful.

Thank you,
Matt

Re: Error importing flows from a registry instance to a fresh nifi instance

alan18080 — Thu, 23 May 2024 11:52:51 GMT

Hello,

Nifi registry: apache/nifi-registry;0.8.0

Steps:

We deploy nifi and nifi-registry in kubernetes cluster.

We set up nifi-registry with postgresql as flowprovider.

We create a PG with con flows from nifi and start version with nifi-registry.

We delete all deployments and pvc (nifi and nifi-registry) from kubernetes but we keep postgresql database.

We deploy again nifi and nifi-registry

We see in nifi-registry the PG that we versioned

We try to import in nifi the PG from nifi-registry and we get the message "

The Flow Registry with ID ? reports that no Flow exists with Bucket ?, Flow ?"

Thanks for the support.

Re: Error importing flows from a registry instance to a fresh nifi instance

MattWho — Thu, 23 May 2024 12:57:48 GMT

@alan18080

The Postgres DB only holds metadata and does not contain the actual datflow in NiFi-registry. The version controlled dataflows are stored in the configured FlowPersistenceProvider. So if you are not preserving the actual flow contents, then the metadata loaded from your postgresSQL will not find it after redeployment.

I would also recommend upgrading your NiFi-Registry and NiFi versions. NiFi-Registry is going on 4 years old.

Please help our community thrive. If you found any of the suggestions/solutions provided helped you with solving your issue or answering your question, please take a moment to login and click "Accept as Solution" on one or more of them that helped.

Thank you,
Matt

Re: Error importing flows from a registry instance to a fresh nifi instance

DianaTorres — Thu, 23 May 2024 21:34:23 GMT

@alan18080 Has the reply helped resolve your issue? If so, please mark the appropriate reply as the solution, as it will make it easier for others to find the answer in the future. Thanks.