Can an older Kafka client (1.1) talk to a newer broker (2.0) and can a newer client (2.0) talk to an older broker (1.1)?

• A. True
• B. False
• C. Only older client to newer broker is supported
• D. Only newer client to older broker is supported

Answer: (A)

Communication between Kafka clients and brokers relies on a negotiated set of API versions. When a client connects, the broker tells it which API versions are supported, and the client then uses a compatible subset of those APIs. This design lets a newer broker still handle requests from an older client using the older API calls it supports, and it lets a newer client operate with an older broker by sticking to the APIs the broker understands. As a result, both directions work, with the caveat that you won’t be able to use features introduced in newer APIs when either side is on an older version.