A UIM hub which has been running successfully for a number of hours or several days may suddenly turn red or disappear from the infrastructure. Restarting the hub's robot service restores connectivity.
An examination of the hub.log at level 3 or higher will show the following error messages, usually repeating approximately every three minutes:
hub: Subscribe error: queue prediction_engine.hubname.PREDICTION_CONFIG already has a subscriber
hub: Subscribe error: queue baseline_engine.hubname.BASELINE_CONFIG already has a subscriber
The baseline_engine and prediction_engine probes which ship with UIM 8.4 will resolve this issue, so an upgrade to UIM 8.4 is recommended.
For users who are unable to upgrade immediately, hotfixed versions of the baseline_engine and prediction_engine probes can be downloaded from the following page:
UIM Hotfix Index