NotEnoughReplicasException: The size of the current ISR Set(2) is insufficient to satisfy the min.isr requirement of 3

1
votes

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" ?

Update #1

Topic: topic-ack-all    PartitionCount: 4       ReplicationFactor: 3    Configs:            
        Topic: topic-ack-all    Partition: 0    Leader: 1       Replicas: 1,2,3 Isr: 1,2,3  
        Topic: topic-ack-all    Partition: 1    Leader: 1       Replicas: 2,3,1 Isr: 1,2,3  
        Topic: topic-ack-all    Partition: 2    Leader: 1       Replicas: 3,1,2 Isr: 1,2,3  
        Topic: topic-ack-all    Partition: 3    Leader: 1       Replicas: 1,3,2 Isr: 1,2,3

Update 2

Topic: __consumer_offsets       PartitionCount: 50      ReplicationFactor: 1    Configs: compression.type=producer,cleanup.policy=compact,segment.bytes=104857600
    Topic: __consumer_offsets       Partition: 0    Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 1    Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 2    Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 3    Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 4    Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 5    Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 6    Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 7    Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 8    Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 9    Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 10   Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 11   Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 12   Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 13   Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 14   Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 15   Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 16   Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 17   Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 18   Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 19   Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 20   Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 21   Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 22   Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 23   Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 24   Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 25   Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 26   Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 27   Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 28   Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 29   Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 30   Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 31   Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 32   Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 33   Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 34   Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 35   Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 36   Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 37   Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 38   Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 39   Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 40   Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 41   Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 42   Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 43   Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 44   Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 45   Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 46   Leader: 3       Replicas: 3     Isr: 3
    Topic: __consumer_offsets       Partition: 47   Leader: 1       Replicas: 1     Isr: 1
    Topic: __consumer_offsets       Partition: 48   Leader: 2       Replicas: 2     Isr: 2
    Topic: __consumer_offsets       Partition: 49   Leader: 3       Replicas: 3     Isr: 3
1
apache-kafkaconfluent-platform
Can you add the output of bin\windows\kafka-topics --zookeeper 127.0.0.1:2181 --describe? – Mickael Maison
@MickaelMaison, just added. Thanks – Nag
and also, what is the reason "Configs" flag shows some status sometimes and no status other times ? – Nag
The error is with the __consumer_offsets topic when you run the consume. Can you add the description of that topic too? – Mickael Maison
@MickaelMaison I just added, thanks – Nag

1 Answers

5
votes

From the output you pasted, it looks like the __consumer_offsets topic was created with a single replica.

It also looks like your broker are setup with min.insync.replicas = 3.

With this configuration, it's expected to get NotEnoughReplicasException if a consumer commits offsets.

The __consumer_offsets topic is created automatically when the first consumer connect to the cluster. One common way to end up in your situation is if you ran a consumer while you only had a single broker running. In that case the __consumer_offsets would be created with a single replica.

Assuming it's a dev environment, the easiest way to get back to a valid state is to delete the __consumer_offsets and rerun your consumer while all 3 brokers.are up.