Due to Apache Kafka's widespread integration into enterprise-level infrastructures, monitoring Kafka performance at scale has become an increasingly important task. It can be challenging to understand what is happening in Kafka - both at the application level and lag performance, to successfully root cause/troubleshoot problems. To perform effective diagnosis, meaningful insights and visibility throughout all levels of the cluster are a must. This talk will take a dive into what metrics or indicators matter most while running Kafka at Scale focusing on Lag performance. How to interpret and correlate these indicators, build dashboards and configure meaningful alerts to identify a probable issue to take place. This talk concludes with the idea of doing trend analysis to detect anomalies for long-running Kafka pipelines.