Kylin / Web UI not loading in Docker

Summary

I'm trying to run Apache MDX for Kylin in a Docker container (in order to experiment / test it out) following the instructions on the Apache page, but it doesn't seem to work properly. Specifically, when I try to access the Web UI, I see a blank page that seems like it's trying to load something, but never gets there (in contrast, if the container is not running at all, the page fails immediately with something like "The connection was reset").

The container itself seems to be working OK (for example, the MDX, Hadoop etc. interfaces load up OK).

(Possibly) Relevant details

• I'm running Docker 24.0.5 on Kubuntu 22.04.

• The image I'm using is apachekylin/apache-kylin-standalone:kylin-4.0.1-mondrian, but I also tried apachekylin/apache-kylin-standalone:4.0.0 and it has the same problem exactly.

• I've tried different browsers (Firefox, Chromium, Falkon) to rule out a problem with that.

• I can enter the container and tested that the network connection works (I can ping Google for example). I also confirmed that the ports used (7070, 7080, 50070, 8088) are not blocked in any way.

• The MDX interface (port 7080) loads up, but if I try to log in, I get the following error:

  [MDX-01050001] Can't connect to Kylin. Please contact your administrator to check that Kylin is working properly.

  which sort of makes sense if Kylin is not working properly. The error details (pastebin) might contain some useful clues, but I can't tell.

• The Hadoop Web UI (port 8088) loads up, but reports the node as UNHEALTHY. Not sure what that means. The "Health-report" says:

  1/1 local-dirs are bad: /data/hadoop/nm-local-dir; 1/1 log-dirs are bad: /home/admin/hadoop-2.8.5/logs/userlogs

• I've tried restarting Kylin from within the container (pastebin), but it makes no difference. I started getting a message about the version of Spark today (wasn't there when I tried the same steps the other day), but I'm not sure if that's related to the problem.

I'm not sure what else to try at this point. Any suggestions on how to identify the problem? Please let me know in the comments if there's any other potentially useful information to include here.

Additional inforelating to the answer by David Beavon

Confirmed that the MDX service is running:

# bash mdx-kylin-4.0.1-beta/bin/mdx.sh startWorking directory: /home/admin/mdx-kylin-4.0.1-betaMDX context path: /Start Kylin MDX...MDX_HOME=/home/admin/mdx-kylin-4.0.1-betaMDX_CONF=/home/admin/mdx-kylin-4.0.1-beta/confJAVA_HOME has been set,it's /home/admin/jdk1.8.0_141JAVA=/home/admin/jdk1.8.0_141/bin/javaUse database: mysqlSemantic Service is already started.

netstat shows the expected ports to be listening, both in the Docker container and on my machine.

Logs in Docker container:

/home/admin/mdx-kylin-4.0.1-beta/logs/semantic.log

/home/admin/mdx-kylin-4.0.1-beta/logs/mdx.log