Kafka Tools

https://cwiki.apache.org/confluence/display/KAFKA/System+Tools

https://cwiki.apache.org/confluence/display/KAFKA/Replication+tools

http://kafka.apache.org/documentation.html#quickstart

http://kafka.apache.org/documentation.html#operations

 

为了便于使用。kafka提供了比較强大的Tools。把常常须要使用的整理一下

 

开关kafka Server

bin/kafka-server-start.sh config/server.properties
bin/kafka-server-stop.sh
JMX_PORT=9999 nohup bin/kafka-server-start.sh config/server.properties &

 

topic相关

bin/kafka-topics.sh --create --zookeeper localhost:2181 --replication-factor 1 --partitions 1 --topic test
bin/kafka-topics.sh --list --zookeeper localhost:2181

describe topic的具体情况

bin/kafka-topics.sh --describe --zookeeper localhost:2181 --topic test

改动topic的partition，仅仅能添加

bin/kafka-topics.sh --alter --zookeeper localhost:2181 --partitions 3 --topic test

到0.8.2才正式支持删除topic，当前是beta版

bin/kafka-topics.sh --zookeeper zk_host:port/chroot --delete --topic my_topic_name

查看有问题的partition

bin/kafka-topics.sh --describe --zookeeper localhost:2181 --unavailable-partitions --topic test

per-topic 改动參数

> bin/kafka-topics.sh --zookeeper localhost:2181 --create --topic my-topic --partitions 1 
        --replication-factor 1 --config max.message.bytes=64000 --config flush.messages=1

> bin/kafka-topics.sh --zookeeper localhost:2181 --alter --topic my-topic 
    --config max.message.bytes=128000

> bin/kafka-topics.sh --zookeeper localhost:2181 --alter --topic my-topic 
    --deleteConfig max.message.bytes

 

集群扩展
集群扩展。对于broker还是比較简单的，可是现有的topic上的partition是不会做自己主动迁移的
须要手工做迁移，但kafka提供了比較方便的工具。

--generate，生成參考的迁移计划
given a list of topics and a list of brokers，工具会给出迁徙方案

把topic全然迁移到新的brokers

> cat topics-to-move.json
{"topics": [{"topic": "foo1"},
            {"topic": "foo2"}],
 "version":1
}

> bin/kafka-reassign-partitions.sh --zookeeper localhost:2181 --topics-to-move-json-file topics-to-move.json --broker-list "5,6" --generate 
Current partition replica assignment

{"version":1,
 "partitions":[{"topic":"foo1","partition":2,"replicas":[1,2]},
               {"topic":"foo1","partition":0,"replicas":[3,4]},
               {"topic":"foo2","partition":2,"replicas":[1,2]},
               {"topic":"foo2","partition":0,"replicas":[3,4]},
               {"topic":"foo1","partition":1,"replicas":[2,3]},
               {"topic":"foo2","partition":1,"replicas":[2,3]}]
}

Proposed partition reassignment configuration

{"version":1,
 "partitions":[{"topic":"foo1","partition":2,"replicas":[5,6]},
               {"topic":"foo1","partition":0,"replicas":[5,6]},
               {"topic":"foo2","partition":2,"replicas":[5,6]},
               {"topic":"foo2","partition":0,"replicas":[5,6]},
               {"topic":"foo1","partition":1,"replicas":[5,6]},
               {"topic":"foo2","partition":1,"replicas":[5,6]}]
}

给出当前的assignment情况和，迁移方案

我们能够同一时候保存当前的assignment情况和迁移方案。当前的assignment情况能够用于rollback

--execute，開始运行迁移

> bin/kafka-reassign-partitions.sh --zookeeper localhost:2181 --reassignment-json-file expand-cluster-reassignment.json --execute
Current partition replica assignment

{"version":1,
 "partitions":[{"topic":"foo1","partition":2,"replicas":[1,2]},
               {"topic":"foo1","partition":0,"replicas":[3,4]},
               {"topic":"foo2","partition":2,"replicas":[1,2]},
               {"topic":"foo2","partition":0,"replicas":[3,4]},
               {"topic":"foo1","partition":1,"replicas":[2,3]},
               {"topic":"foo2","partition":1,"replicas":[2,3]}]
}

Save this to use as the --reassignment-json-file option during rollback
Successfully started reassignment of partitions
{"version":1,
 "partitions":[{"topic":"foo1","partition":2,"replicas":[5,6]},
               {"topic":"foo1","partition":0,"replicas":[5,6]},
               {"topic":"foo2","partition":2,"replicas":[5,6]},
               {"topic":"foo2","partition":0,"replicas":[5,6]},
               {"topic":"foo1","partition":1,"replicas":[5,6]},
               {"topic":"foo2","partition":1,"replicas":[5,6]}]
}

--verify，check当前的迁移状态

> bin/kafka-reassign-partitions.sh --zookeeper localhost:2181 --reassignment-json-file expand-cluster-reassignment.json --verify
Status of partition reassignment:
Reassignment of partition [foo1,0] completed successfully
Reassignment of partition [foo1,1] is in progress
Reassignment of partition [foo1,2] is in progress
Reassignment of partition [foo2,0] completed successfully
Reassignment of partition [foo2,1] completed successfully 
Reassignment of partition [foo2,2] completed successfully

选择topic的某个partition的某些replica进行迁徙

moves partition 0 of topic foo1 to brokers 5,6 and partition 1 of topic foo2 to brokers 2,3

> cat custom-reassignment.json
{"version":1,"partitions":[{"topic":"foo1","partition":0,"replicas":[5,6]},{"topic":"foo2","partition":1,"replicas":[2,3]}]}

> bin/kafka-reassign-partitions.sh --zookeeper localhost:2181 --reassignment-json-file custom-reassignment.json --execute
Current partition replica assignment

{"version":1,
 "partitions":[{"topic":"foo1","partition":0,"replicas":[1,2]},
               {"topic":"foo2","partition":1,"replicas":[3,4]}]
}

Save this to use as the --reassignment-json-file option during rollback
Successfully started reassignment of partitions
{"version":1,
 "partitions":[{"topic":"foo1","partition":0,"replicas":[5,6]},
               {"topic":"foo2","partition":1,"replicas":[2,3]}]
}

brokers下线

当前版本号不支持下线的规划，须要到0.8.2才支持，这须要把一个broker上的replica清空

添加replication factor

partition 0的replica数从1增长到3，当前replica存在broker5，在broker6，7上添加replica

> cat increase-replication-factor.json
{"version":1,
 "partitions":[{"topic":"foo","partition":0,"replicas":[5,6,7]}]}

> bin/kafka-reassign-partitions.sh --zookeeper localhost:2181 --reassignment-json-file increase-replication-factor.json --execute
Current partition replica assignment

{"version":1,
 "partitions":[{"topic":"foo","partition":0,"replicas":[5]}]}

Save this to use as the --reassignment-json-file option during rollback
Successfully started reassignment of partitions
{"version":1,
 "partitions":[{"topic":"foo","partition":0,"replicas":[5,6,7]}]}

 

Producer console

> bin/kafka-console-producer.sh --broker-list localhost:9092 --topic test 
This is a message
This is another message

后面能够随意的输入message。都会发到broker的topic中

 

Comsumer console

bin/kafka-console-consumer.sh --zookeeper localhost:2181 --topic test --from-beginning

从头读这个topic，能够反复读到全部数据
我在想为啥，每次都能replay。原来每次都是随机产生一个groupid
consumerProps.put("group.id","console-consumer-" + new Random().nextInt(100000))

 

Consumer Offset Checker

这个会显示出consumer group的offset情况， 必须參数为--group。 不指定--topic，默觉得全部topic

Displays the:  Consumer Group, Topic, Partitions, Offset, logSize, Lag, Owner for the specified set of Topics and Consumer Group

bin/kafka-run-class.sh kafka.tools.ConsumerOffsetChecker

required argument: [group]
Option Description
------ -----------
--broker-info Print broker info
--group Consumer group.
--help Print this message.
--topic Comma-separated list of consumer
   topics (all topics if absent).
--zkconnect ZooKeeper connect string. (default: localhost:2181)

Example,

bin/kafka-run-class.sh kafka.tools.ConsumerOffsetChecker --group pv

Group           Topic                          Pid Offset          logSize         Lag             Owner
pv              page_visits                    0   21              21              0               none
pv              page_visits                    1   19              19              0               none
pv              page_visits                    2   20              20              0               none

 

 

Export Zookeeper Offsets

将Zk中的offset信息以以下的形式打到file里面去

A utility that retrieves the offsets of broker partitions in ZK and prints to an output file in the following format:

/consumers/group1/offsets/topic1/1-0:286894308
/consumers/group1/offsets/topic1/2-0:284803985

bin/kafka-run-class.sh kafka.tools.ExportZkOffsets

required argument: [zkconnect]
Option Description
------ -----------
--group Consumer group.
--help Print this message.
--output-file Output file
--zkconnect ZooKeeper connect string. (default: localhost:2181)

 

Update Offsets In Zookeeper

这个挺实用，用于replay, kafka的文档有点坑爹，看了不知道咋用。还是看源代码才看明确

A utility that updates the offset of every broker partition to the offset of earliest or latest log segment file, in ZK.

bin/kafka-run-class.sh kafka.tools.UpdateOffsetsInZK

USAGE: kafka.tools.UpdateOffsetsInZK$ [earliest | latest] consumer.properties topic

Example，

bin/kafka-run-class.sh kafka.tools.UpdateOffsetsInZK earliest config/consumer.properties  page_visits

Group           Topic                          Pid Offset          logSize         Lag             Owner
pv              page_visits                    0   0               21              21              none
pv              page_visits                    1   0               19              19              none
pv              page_visits                    2   0               20              20              none

能够看到offset已经被清0。Lag=logSize

 

更加直接的方式是。直接去Zookeeper里面看

通过zkCli.sh连上后，通过ls查看

Broker Node Registry

/brokers/ids/[0...N] --> host:port (ephemeral node)

Broker Topic Registry

/brokers/topics/[topic]/[0...N] --> nPartions (ephemeral node)

Consumer Id Registry

/consumers/[group_id]/ids/[consumer_id] --> {"topic1": #streams, ..., "topicN": #streams} (ephemeral node)

Consumer Offset Tracking

/consumers/[group_id]/offsets/[topic]/[broker_id-partition_id] --> offset_counter_value ((persistent node)

Partition Owner registry

/consumers/[group_id]/owners/[topic]/[broker_id-partition_id] --> consumer_node_id (ephemeral node)