Using inconsistent location URL for Registry Client on different NiFi instances will break ability to import version controlled flows that contain nested version controlled flows.
on NiFi instance 1, configure "Registry Client" location URL with https://<nifi-registry>:<port>/
on NiFi instance 2, configure "Registry Client" location URL with https://<nifi-registry>:<port>
notice that one contains a trailing "/"
On one of your NiFi instances, create a Process Group (PG).
Inside that PG, create another "sub-PG".
Start version control of sub-PG.
Go back to parent PG and also start version control on that "PG".
Go to your other NiFi instance and try to "import" the "PG" version controlled flow.
Import will fail and throw following error in nifi-user.log:
o.a.n.w.a.c.IllegalArgumentExceptionMapper java.lang.IllegalArgumentException: The Flow Registry with ID <UUID> reports that no Flow exists with Bucket <UUID>, Flow <UUID, Version 2. Returning Bad Request response.
Even though registry does include the referenced UUIDs in that log output.