MLflow Artifacts Storing But Not Listing In UI

Question

I've run into an issue using MLflow server. When I first ran the command to start an mlflow server on an ec2 instance, everything worked fine. Now, although logs and artifacts are being stored to postgres and s3, the UI is not listing the artifacts. Instead, the artifact section of the UI shows:

Loading Artifacts Failed
Unable to list artifacts stored under <s3-location> for the current run. Please contact your tracking server administrator to notify them of this error, which can happen when the tracking server lacks permission to list artifacts under the current run's root artifact directory.

But when I check in s3, I see the artifact in the s3 location that the error shows. What could possibly have started causing this as it used to work not too long ago and nothing was changed on the ec2 that is hosting mlflow?

Answer 1

I found the answer. The error was that mlflow could not find boto3, so a conda installation of that worked. The logs for this were buried and hard to find in stdout.