Scale or Signal? How One Config Change Rewrites Kafka's Behaviour
"Is your system designed for Teamwork or Broadcast? The difference is just one line of code." Imagine you’re debugging a critical production issue. You’re staring at the logs, coffee in hand, trying to track an order through your system. You have a Kafka Topic named orders with 2 Partitions (P1 & P2) . You publish two messages: Order #101 (lands on Partition P1). Order #102 (lands on Partition P2). You fire up two PODs of your microservice— let’s call them Consumer A and Consumer B — to process these orders. You watch the terminal, waiting for them to light up. Consumer A picks up Order #101 . Consumer B picks up Order #102 . But then you notice something unsettling. Consumer A never saw Order #102. And Consumer B completely ignored Order #101. If you come from a traditional pub-sub world (like JMS or ActiveMQ), the panic starts to set in. "Did the message get lost? Why didn't Consumer A see both orders? Is the partition broken?" The short answer to ...