Replicas and Isr are both a comma separated list of broker IDs. So in this output, I am seeing that you have two Kafka brokers with IDs 1 and 2. You have a topic, capture, with 16 partitions at replication factor 1 (1 replica per partition). The broker with ID 2 is not online, which is why it shows in the Replica list for some partitions (meaning that it is assigned to be a replica), but not in the Isr list (which would indicate that it is currently in-sync).
The Leader field is the broker ID which is currently the leader for that partition. For the partitions that are assigned to broker 1, you see that broker 1 is the leader. For the partitions that are assigned to broker 2, the leader is listed as -1, which indicates that there is no available leader. These partitions are considered offline and cannot be produced to or consumed from. When broker 2 comes back online, the controller will perform an unclean leader election and select broker 2 (the only replica available) as the leader for those partitions. -Todd On Sun, Nov 22, 2015 at 11:39 AM, Jan Algermissen < algermissen1...@icloud.com> wrote: > Hi, > > I have a topic with 16 partitions that shows the following output for > > kafka-topics.sh --zookeeper xxxxx:2181 --topic capture --describe > > Can anyone explain to me what the difference in replicas means and what > Leader of -1 means? > > In the logs of my producer I see that no messages seem to be sent to the > partitions with '-1' and th eproducer buffer becomes exhausted afetr a > while (maybe that is related?) > > Jan > > Topic:capture PartitionCount:16 ReplicationFactor:1 > Configs: > > Topic: capture Partition: 0 Leader: 1 Replicas: 1 > Isr: 1 > Topic: capture Partition: 1 Leader: 1 Replicas: 1 > Isr: 1 > Topic: capture Partition: 2 Leader: -1 Replicas: 2 > Isr: > Topic: capture Partition: 3 Leader: 1 Replicas: 1 > Isr: 1 > Topic: capture Partition: 4 Leader: -1 Replicas: 2 > Isr: > Topic: capture Partition: 5 Leader: 1 Replicas: 1 > Isr: 1 > Topic: capture Partition: 6 Leader: -1 Replicas: 2 > Isr: > Topic: capture Partition: 7 Leader: 1 Replicas: 1 > Isr: 1 > Topic: capture Partition: 8 Leader: -1 Replicas: 2 > Isr: > Topic: capture Partition: 9 Leader: 1 Replicas: 1 > Isr: 1 > Topic: capture Partition: 10 Leader: -1 Replicas: 2 > Isr: > Topic: capture Partition: 11 Leader: 1 Replicas: 1 > Isr: 1 > Topic: capture Partition: 12 Leader: -1 Replicas: 2 > Isr: > Topic: capture Partition: 13 Leader: 1 Replicas: 1 > Isr: 1 > Topic: capture Partition: 14 Leader: -1 Replicas: 2 > Isr: > Topic: capture Partition: 15 Leader: 1 Replicas: 1 > Isr: 1
