Unable to communicate with NiFi

[#1]

Hello, I'm new to NiFi and I'm experiencing problems during the installation phase. Unfortunately, I can't connect to the NiFi web interface. I've scoured the internet, but I still can't resolve the issue. I'm trying to install NiFi version 2.0.0-M4, and when I try to access the web interface by typing https://localhost:8443/nifi in the browser, I continuously get the error message "Unable to communicate with NiFi."

Some forums suggest waiting for a bit to allow NiFi to fully start and then trying again, but that hasn't solved the problem either. I also tried using HTTP instead of HTTPS, but that didn't work either. There are no error messages in the nifi-app.log file, and everything seems to be running normally.

The strange part is that I successfully followed the same installation steps on my colleague's computer, and it worked fine. However, when I follow the exact same steps on my own computer, it doesn't work. As for dependencies, I have both Java 8 and Java 23 installed on my machine, but still no luck. Could you help me out with this issue? Thanks in advance!

If you need further help with troubleshooting the issue, feel free to ask!

[#2]

@Suayb 

NiFi- 2.x requires Java 21
The make sure your NiFi is starting with Java 21 and not another version of Java.
You configure a specific java in the NiFi.bootstrap.conf file.  By default in that file java is set to "java=java" which uses system default java.  You could could change this to "java=<path to java 21 bin dir>/java"

If above does not solve issue start reviewing the nifi-bootstrap.log, nifi-app.log, and nifi-request.log for any relevant details.

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

[#3]

Greetings Matt,

First of all, thank you for your fast reply and suggestions. I tried what you suggested, but unfortunately the result didn't change. I will share some screenshots with you. Maybe they can help.

[#4]

@Suayb I see no ERROR logging in anything you have shared.

The snippet of the nifi-app.log you shared only shows that NiFi is still starting up.
NiFi is not fully up and the UI is not accessible until you see the following lines output in the nifi-app.log:

2024-10-17 09:24:32,817 INFO [main] org.apache.nifi.web.server.JettyServer Started Server on https://<hostname>:8443/nifi
2024-10-17 09:24:32,818 INFO [main] org.apache.nifi.BootstrapListener Successfully initiated communication with Bootstrap
2024-10-17 09:24:32,819 INFO [main] org.apache.nifi.NiFi Started Application Controller in 11.878 seconds (11878131211 ns)

Are you seeing above in your nifi-app.log?

Are you seeing any ERROR lines in any of you logs?
are you seeing any disk space issues?

Thanks,
Matt