Surprise, in the UI, of a working instance of NiFi 1.28.1, I get:
Unable to communicate with NiFi
Please ensure the application is running and check the logs for any
errors.
I have changed since it worked some logic inside a custom processor that
is neither of the following ones.
Checking the logs, I find nothing except in */nifi-app.log/* the
following. The two processors are my own.
2025-07-21 17:14:22,787 ERROR [Timer-Driven Process Thread-2]
c.i.processor.CreateAttributes
CreateAttributes[id=90508e0f-0195-1000-1579-ff0c3317c9a3]
Encountering difficulty starting. (Validation State is INVALID:
['Relationship Success' is invalid because Relationship
'Success' is not connected to any component and is not
auto-terminated]).
Will continue trying to start.
2025-07-21 17:14:22,787 ERROR [Timer-Driven Process Thread-8]
c.i.processor.SplitHl7v4Resources
SplitHl7v4Resources[id=ed6de974-0191-1000-fa4b-0830f49ec895]
Encountering difficulty starting. (Validation State is INVALID:
['Relationship ready--resource split out' is invalid because
Relationship 'ready--resource split out' is not connected to any
component and is not auto-terminated,
'Relationship failed--no Bundle' is invalid because
Relationship 'failed--no Bundle' is not connected to any component
and is not auto-terminated]).
Will continue trying to start.
I don't understand why either of these processor instances would have
lost relationship-arc connections with other components though doubtless
I did something to break (but what?).
What I would like to do is to doctor /*flow.xml.gz*/ to "fix" whatever
is needed to get back up and running (rather than removing my flow(s)
and starting from scratch. I have done similar things in the past
successfully (unzipping, editing, then re-zipping), but I do not know
how to "trick out" relationships. Also, I don't actually remember what
components these might be connected to because the flow(s) are non
trivial despite that I am able to find the instances in the unzipped
/*flow.xml*/:
russ@tirion ~/dev/nifi/nifi-1.28.1/conf $ fgrep
90508e0f-0195-1000-1579-ff0c3317c9a3 flow.xml [CreateAttributes]
<id>90508e0f-0195-1000-1579-ff0c3317c9a3</id>
<destinationId>90508e0f-0195-1000-1579-ff0c3317c9a3</destinationId>
russ@tirion ~/dev/nifi/nifi-1.28.1/conf $ fgrep
ed6de974-0191-1000-fa4b-0830f49ec895 flow.xml [SplitHl7v4Resources]
<id>ed6de974-0191-1000-fa4b-0830f49ec895</id>
<sourceId>ed6de974-0191-1000-fa4b-0830f49ec895</sourceId>
<sourceId>ed6de974-0191-1000-fa4b-0830f49ec895</sourceId>
<sourceId>ed6de974-0191-1000-fa4b-0830f49ec895</sourceId>
<sourceId>ed6de974-0191-1000-fa4b-0830f49ec895</sourceId>
<sourceId>ed6de974-0191-1000-fa4b-0830f49ec895</sourceId>
<destinationId>ed6de974-0191-1000-fa4b-0830f49ec895</destinationId>
Any suggestion would be appreciated.
Russ
