Kafka Monitor

Kafka Monitor is a framework to implement and execute long-running kafka system tests in a real cluster. It complements Kafka’s existing system tests by capturing potential bugs or regressions that are only likely to occur after prolonged period of time or with low probability. Moreover, it allows you to monitor Kafka cluster using end-to-end pipelines to obtain a number of derived vital stats such as end-to-end latency, service availability and message loss rate. You can easily deploy Kafka Monitor to test and monitor your Kafka cluster without requiring any change to your application.

Kafka Monitor can automatically create the monitor topic with the specified config and increase partition count of the monitor topic to ensure partition# >= broker#. It can also reassign partition and trigger preferred leader election to ensure that each broker acts as leader of at least one partition of the monitor topic. This allows Kafka Monitor to detect performance issue on every broker without requiring users to manually manage the partition assignment of the monitor topic.

Getting Started

Prerequisites

Kafka Monitor requires Gradle 2.0 or higher. Java 7 should be used for building in order to support both Java 7 and Java 8 at runtime.

Kafka Monitor supports Apache Kafka 0.8 to 2.0:

• Use branch 0.8.2.2 to work with Apache Kafka 0.8
• Use branch 0.9.0.1 to work with Apache Kafka 0.9
• Use branch 0.10.2.1 to work with Apache Kafka 0.10
• Use branch 0.11.x to work with Apache Kafka 0.11
• Use branch 1.0.x to work with Apache Kafka 1.0
• Use branch 1.1.x to work with Apache Kafka 1.1
• Use master branch to work with Apache Kafka 2.0

Configuration Tips

• We advise advanced users to run Kafka Monitor with ./bin/kafka-monitor-start.sh config/kafka-monitor.properties. The default kafka-monitor.properties in the repo provides an simple example of how to monitor a single cluster. You probably need to change the value of zookeeper.connect and bootstrap.servers to point to your cluster.

• The full list of configs and their documentation can be found in the code of Config class for respective service, e.g. ProduceServiceConfig.java and ConsumeServiceConfig.java.

• You can specify multiple SingleClusterMonitor in the kafka-monitor.properties to monitor multiple Kafka clusters in one Kafka Monitor process. As another advanced use-case, you can point ProduceService and ConsumeService to two different Kafka clusters that are connected by MirrorMaker to monitor their end-to-end latency.

• Kafka Monitor by default will automatically create the monitor topic based on the e.g. topic-management.replicationFactor and topic-management.partitionsToBrokersRatio specified in the config. replicationFactor is 1 by default and you probably want to change it to the same replication factor as used for your existing topics. You can disable auto topic creation by setting produce.topic.topicCreationEnabled to false.

• Kafka Monitor can automatically increase partition count of the monitor topic to ensure partition# >= broker#. It can also reassign partition and trigger preferred leader election to ensure that each broker acts as leader of at least one partition of the monitor topic. To use this feature, use either EndToEndTest or TopicManagementService in the properties file.

Build Kafka Monitor

$ git clone https://github.com/linkedin/kafka-monitor.git
$ cd kafka-monitor 
$ ./gradlew jar

Start KafkaMonitor to run tests/services specified in the config file

$ ./bin/kafka-monitor-start.sh config/kafka-monitor.properties

Run Kafka Monitor with arbitrary producer/consumer configuration (e.g. SASL enabled client)

Edit config/kafka-monitor.properties to specify custom configurations for producer in the key/value map produce.producer.props in config/kafka-monitor.properties. Similarly specify configurations for consumer as well. The documentation for producer and consumer in the key/value maps can be found in the Apache Kafka wiki.

$ ./bin/kafka-monitor-start.sh config/kafka-monitor.properties

Run SingleClusterMonitor app to monitor kafka cluster

Metrics produce-availability-avg and consume-availability-avg demonstrate whether messages can be properly produced to and consumed from this cluster. See Service Overview wiki for how these metrics are derived.

$ ./bin/single-cluster-monitor.sh --topic test --broker-list localhost:9092 --zookeeper localhost:2181

Run MultiClusterMonitor app to monitor a pipeline of Kafka clusters connected by MirrorMaker

Edit config/multi-cluster-monitor.properties to specify the right broker and zookeeper url as suggested by the comment in the properties file

Metrics produce-availability-avg and consume-availability-avg demonstrate whether messages can be properly produced to the source cluster and consumed from the destination cluster. See config/multi-cluster-monitor.properties for the full jmx path for these metrics.

$ ./bin/kafka-monitor-start.sh config/multi-cluster-monitor.properties

Get metric values (e.g. service availability, message loss rate) in real-time as time series graphs

Open localhost:8000/index.html in your web browser

You can edit webapp/index.html to easily add new metrics to be displayed.

Query metric value (e.g. produce availability and consume availability) via HTTP request

curl localhost:8778/jolokia/read/kmf.services:type=produce-service,name=*/produce-availability-avg

curl localhost:8778/jolokia/read/kmf.services:type=consume-service,name=*/consume-availability-avg

You can query other JMX metric value as well by substituting object-name and attribute-name of the JMX metric in the query above.

Run checkstyle on the java code

./gradlew checkstyleMain checkstyleTest

Build IDE project

./gradlew idea
./gradlew eclipse

Wiki

• Motivation
• Design Overview
• Service and App Overview
• Future Work