Hi Nag, ISR is the replicas that are in sync with the leader, and there's a different ISR set for each partition of a given topic. If you use `kafka/bin/kafka-topics --describe --topic <X>` it'll show you the replicas and ISR for each partition.
min.insync.replicas and replication factor are all about preventing data loss. Generally I set min ISR to 2 for a topic with a replication factor of 3 so that one down or struggling broker doesn't prevent producers writing to topics, but I still have a replica of the data in case the broker acting as leader goes down - a new partition leader can only be elected from the insync replicas. On Tue, Jul 7, 2020 at 7:39 PM Nag Y <andriod.nag.u...@gmail.com> wrote: > I had the following setup Brokers : 3 - all are up and running with > min.insync.replicas=3. > > I created a topic with the following configuration > > bin\windows\kafka-topics --zookeeper 127.0.0.1:2181 --topic topic-ack-all > --create --partitions 4 --replication-factor 3 > > I triggered the producer with "ack = all" and producer is able to send the > message. However, the problem starts when i start the consumer > > bin\windows\kafka-console-consumer --bootstrap-server > localhost:9094,localhost:9092 --topic topic-ack-all --from-beginning > > The error is > > NotEnoughReplicasException: The size of the current ISR Set(2) is > insufficient to satisfy the min.isr requirement of 3 > NotEnoughReplicasException:The size of the current ISR Set(3) is > insufficient to satisfy the min.isr requirement of 3 for partition __con > > I see two kinds of errors here . I went though the documentation and had > also understaning about "min.isr", However, these error messages are not > clear . > > 1. What does it mean by current ISR set ? Is it different for each topic > and what it signifies ? > 2. I guess min.isr is same as min.insync.replicas . I hope is should > have value at least same as "replication factor" ? >
