3 AZ Kafka is the safest, but I've run several 2.5 clusters just fine. (cluster stretched across 2 AZs with a tiebreaker ZK in a 3rd AZ to maintain quorum in the event that you lose an AZ)
(WarpStream Founder) That's fair, but we think people shouldn't have to choose between multiple AZs and costs. All cloud providers recommend that critical workloads running in cloud environments should run in more than one AZ.
> Cloud economics – by design, Kafka’s replication strategy will rack up massive inter AZ bandwidth costs.
You're no more or less forced to put Kafka replicas in different AZs than you would be with an alternative.