Kafka Manager (Universal Package)

// With RPM & DEB files //

Built from Source Code : https://github.com/yahoo/kafka-manager/

A tool for managing Apache Kafka.

It supports the following :

• Manage multiple clusters
• Easy inspection of cluster state (topics, consumers, offsets, brokers, replica distribution, partition distribution)
• Run preferred replica election
• Generate partition assignments with option to select brokers to use
• Run reassignment of partition (based on generated assignments)
• Create a topic with optional topic configs (0.8.1.1 has different configs than 0.8.2+)
• Delete topic (only supported on 0.8.2+ and remember set delete.topic.enable=true in broker config)
• Topic list now indicates topics marked for deletion (only supported on 0.8.2+)
• Batch generate partition assignments for multiple topics with option to select brokers to use
• Batch run reassignment of partition for multiple topics
• Add partitions to existing topic
• Update config for existing topic
• Optionally enable JMX polling for broker level and topic level metrics.
• Optionally filter out consumers that do not have ids/ owners/ & offsets/ directories in zookeeper.

Cluster Management

Topic List

Topic View

Consumer List View

Consumed Topic View

Broker List

Broker View

Requirements

1. Kafka 0.8.. or 0.9.. or 0.10.. or 0.11..
2. Java 8+

Configuration

The minimum configuration is the zookeeper hosts which are to be used for kafka manager state. This can be found in the application.conf file in conf directory. The same file will be packaged in the distribution zip file; you may modify settings after unzipping the file on the desired server.

kafka-manager.zkhosts="my.zookeeper.host.com:2181"

You can specify multiple zookeeper hosts by comma delimiting them, like so:

kafka-manager.zkhosts="my.zookeeper.host.com:2181,other.zookeeper.host.com:2181"

Alternatively, use the environment variable ZK_HOSTS if you don't want to hardcode any values.

ZK_HOSTS="my.zookeeper.host.com:2181"

You can optionally enable/disable the following functionality by modifying the default list in application.conf :

application.features=["KMClusterManagerFeature","KMTopicManagerFeature","KMPreferredReplicaElectionFeature","KMReassignPartitionsFeature"]

• KMClusterManagerFeature - allows adding, updating, deleting cluster from Kafka Manager
• KMTopicManagerFeature - allows adding, updating, deleting topic from a Kafka cluster
• KMPreferredReplicaElectionFeature - allows running of preferred replica election for a Kafka cluster
• KMReassignPartitionsFeature - allows generating partition assignments and reassigning partitions

Consider setting these parameters for larger clusters with jmx enabled :

• kafka-manager.broker-view-thread-pool-size=< 3 * number_of_brokers>
• kafka-manager.broker-view-max-queue-size=< 3 * total # of partitions across all topics>
• kafka-manager.broker-view-update-seconds=< kafka-manager.broker-view-max-queue-size / (10 * number_of_brokers) >

Here is an example for a kafka cluster with 10 brokers, 100 topics, with each topic having 10 partitions giving 1000 total partitions with JMX enabled :

• kafka-manager.broker-view-thread-pool-size=30
• kafka-manager.broker-view-max-queue-size=3000
• kafka-manager.broker-view-update-seconds=30

The follow control consumer offset cache's thread pool and queue :

• kafka-manager.offset-cache-thread-pool-size=< default is # of processors>
• kafka-manager.offset-cache-max-queue-size=< default is 1000>
• kafka-manager.kafka-admin-client-thread-pool-size=< default is # of processors>
• kafka-manager.kafka-admin-client-max-queue-size=< default is 1000>

You should increase the above for large # of consumers with consumer polling enabled. Though it mainly affects ZK based consumer polling.

Kafka managed consumer offset is now consumed by KafkaManagedOffsetCache from the "__consumer_offsets" topic. Note, this has not been tested with large number of offsets being tracked. There is a single thread per cluster consuming this topic so it may not be able to keep up on large # of offsets being pushed to the topic.

Authenticating a User with LDAP

Warning, you need to have SSL configured with Kafka Manager to ensure your credentials aren't passed unencrypted. Authenticating a User with LDAP is possible by passing the user credentials with the Authorization header. LDAP authentication is done on first visit, if successful, a cookie is set. On next request, the cookie value is compared with credentials from Authorization header. LDAP support is through the basic authentication filter.

1. Configure basic authentication

• basicAuthentication.enabled=true
• basicAuthentication.realm=< basic authentication realm>

2. Encryption parameters (optional, otherwise randomly generated on startup) :

• basicAuthentication.salt="some-hex-string-representing-byte-array"
• basicAuthentication.iv="some-hex-string-representing-byte-array"
• basicAuthentication.secret="my-secret-string"

3. Configure LDAP/LDAPS authentication

• basicAuthentication.ldap.enabled=< Boolean flag to enable/disable ldap authentication >
• basicAuthentication.ldap.server=< fqdn of LDAP server>
• basicAuthentication.ldap.port=< port of LDAP server>
• basicAuthentication.ldap.username=< LDAP search username>
• basicAuthentication.ldap.password=< LDAP search password>
• basicAuthentication.ldap.search-base-dn=< LDAP search base>
• basicAuthentication.ldap.search-filter=< LDAP search filter>
• basicAuthentication.ldap.connection-pool-size=< number of connection to LDAP server>
• basicAuthentication.ldap.ssl=< Boolean flag to enable/disable LDAPS>

Example (Online LDAP Test Server):

• basicAuthentication.ldap.enabled=true
• basicAuthentication.ldap.server="ldap.forumsys.com"
• basicAuthentication.ldap.port=389
• basicAuthentication.ldap.username="cn=read-only-admin,dc=example,dc=com"
• basicAuthentication.ldap.password="password"
• basicAuthentication.ldap.search-base-dn="dc=example,dc=com"
• basicAuthentication.ldap.search-filter="(uid=$capturedLogin$)"
• basicAuthentication.ldap.connection-pool-size=10
• basicAuthentication.ldap.ssl=false

Starting the service

After extracting the produced zipfile, and changing the working directory to it, you can run the service like this:

$ bin/kafka-manager

By default, it will choose port 9000. This is overridable, as is the location of the configuration file. For example:

$ bin/kafka-manager -Dconfig.file=/path/to/application.conf -Dhttp.port=8080

Again, if java is not in your path, or you need to run against a different version of java, add the -java-home option as follows:

$ bin/kafka-manager -java-home /usr/local/oracle-java-8

Starting the service with Security

To add JAAS configuration for SASL, add the config file location at start:

$ bin/kafka-manager -Djava.security.auth.login.config=/path/to/my-jaas.conf

NOTE: Make sure the user running kafka manager has read permissions on the jaas config file

Credits

Logo/favicon used is from Apache Kafka.

Most of the utils code has been adapted to work with Apache Curator from Apache Kafka.