[NIFI-8897] Add to Migration Guidance: Copy flow_storage directory

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Component/s: NiFi Registry
• Assignee: Unassigned
• Reporter: Julian Gimbel
• Created: 26/Jul/18 12:52
• Updated: 16/Jul/21 15:14

Description

When we tried to migrate H2 Database from 0.1.0 to 0.2.0 we got the problem that the nifi-registry-app.log showed that all our buckets flows and flow snapshots were successfully copied from legacy to new database.

However when we wanted to import or refresh the repository we could select the flows from the dropdown list, but got an error when we clicked on import.

The log showed the following:

2018-07-26 07:51:21,859 WARN [NiFi Registry Web Server-36] o.a.n.registry.service.RegistryService The specified flow id [d7d8ed4b-68e4-4d88-932c-486863a9f194] does not exist.
2018-07-26 07:51:21,860 INFO [NiFi Registry Web Server-36] o.a.n.r.w.m.ResourceNotFoundExceptionMapper org.apache.nifi.registry.exception.ResourceNotFoundException: The specified flow ID does not exist in this bucket.. Returning Not Found response.

Only after we found this conversation in the Upgrade Mailing List we figured out that we also need to copy HOME/flow_storage directory as the database only contains the metadata but the flow_storage contains the actual data.

It might help people if this peace of information would be added to the migration guidance.