If one can push and consume from one topic in a kafka cluster of 3 brokers running in kubernetes with auto_scaling disabled; can that be used to draw a conclusion that we can successfully push and consume from all the other topics in a cluster?
Total brokers in the cluster: 3
Min-InSyncReplicas: 2
No. of partitions for eahc topic: 25It depends. If you can produce and consume from a particular topic this is a good indication that everything is working in terms of 'communication' (successful consumption from topic_a does not mean that consumption from topic_b will also be OK). However, 'healthy state' is a quite subjective term. Kafka exposes several metrics via JMX for Brokers, Consumers and Producers. Depending on your monitoring requirement you can choose the appropriate metric and decide/judge whether everything is OK (according to your requirements).
Note: If you are using Enterprise Confluent Platform these metrics can also be observed through Confluent Control Center.