All queues are processing messages except tot_rule_config queue on secondary hub.
Release : 8.51
Component : UIM - HUB
1. Make sure alarm_enrichment probe is installed and up running in the same secondary hub
2. If it is not installed, please install nas probe, (alarm_enrichment probe is installed as part of nas probe install)
3. If it is installed, please restart alarm_enrichment probe
Also check the following KB:
Hub queue tot_rule_config is not clearing
https://knowledge.broadcom.com/external/article?articleId=188945