Safety Instructions on Using Kafka

Brief Introduction to Kafka APIs

• Producer API

  Indicates the API defined in org.apache.kafka.clients.producer.KafkaProducer. When kafka-console-producer.sh is used, the API is used by default.

• Consumer API

  Indicates the API defined in org.apache.kafka.clients.consumer.KafkaConsumer. When kafka-console-consumer.sh is used, the API is used by default.

In MRS 3.x or later, Kafka no longer support old Producer or Consumer APIs.

Protocol Description for Accessing Kafka

The protocols used to access Kafka are as follows: PLAINTEXT, SSL, SASL_PLAINTEXT, and SASL_SSL.

When Kafka service is started, the listeners using the PLAINTEXT and SASL_PLAINTEXT protocols are started. You can set ssl.mode.enable to true in Kafka service configuration to start listeners using SSL and SASL_SSL protocols. The following table describes the four protocols:

ACL Settings for a Topic

To view and set topic permission information, run the kafka-acls.sh script on the Linux client. For details, see Managing Kafka User Permissions.

Use of Kafka APIs in Different Scenarios

• Scenario 1: accessing the topic with an ACL

  Used API	User Group	Client Parameter	Server Parameter	Accessed Port
  API	Users need to meet one of the following conditions: In the administrator group In the kafkaadmin group In the kafkasuperuser group In the kafka group and be authorized	security.inter.broker.protocol=SASL_PLAINTEXT sasl.kerberos.service.name = kafka	-	sasl.port (The default number is 21007.)
  		security.protocol=SASL_SSL sasl.kerberos.service.name = kafka	Set ssl.mode.enable to true.	sasl-ssl.port (The default number is 21009.)

• Scenario 2: accessing the topic without an ACL

  Used API	User Group	Client Parameter	Server Parameter	Accessed Port
  API	Users need to meet one of the following conditions: In the administrator group In the kafkaadmin group In the kafkasuperuser group	security.protocol=SASL_PLAINTEXT sasl.kerberos.service.name = kafka	-	sasl.port (The default number is 21007.)
  	Users are in the kafka group.		Set allow.everyone.if.no.acl.found to true. NOTE: In normal mode, the server parameter allow.everyone.if.no.acl.found does not need to be modified.	sasl.port (The default number is 21007.)
  	Users need to meet one of the following conditions: In the administrator group In the kafkaadmin group In the kafkasuperuser group	security.protocol=SASL_SSL sasl.kerberos.service.name = kafka	Set ssl.mode.enable to true.	sasl-ssl.port (The default number is 21009.)
  	Users are in the kafka group.		Set allow.everyone.if.no.acl.found to true. Set ssl.mode.enable to true.	sasl-ssl.port (The default number is 21009.)
  	-	security.protocol=PLAINTEXT	Set allow.everyone.if.no.acl.found to true.	port (The default number is 9092.)
  	-	security.protocol=SSL	Set allow.everyone.if.no.acl.found to true. Set ssl.mode.enable to true.	ssl.port (The default number is 9063.)