Kafka SASL auth setup error: Connection to node 0 (localhost/127.0.0.1:9092) terminated during authentication

[Shantanu Deshmukh]

Hello everyone,

I am trying to setup Kafka SASL authentication on my single node Kafka on
my local machine. version 2.

Here's my Kafka broker JAAS file:

KafkaServer {
   org.apache.kafka.common.security.plain.PlainLoginModule required
   username="admin"
   password="admin"
   user_admin="admin"
   user_dip="dip";
};
Client {
   org.apache.kafka.common.security.plain.PlainLoginModule required
   username="admin"
   password="admin-secret";
};

Zookeeper JAAS file:

Server {
   org.apache.kafka.common.security.plain.PlainLoginModule required
   username="admin"
   password="admin-secret"
   user_admin="admin-secret";
};

Kafka broker properties

listeners=SASL_PLAINTEXT://localhost:9092authroizer.class.name=kafka.security.auth.SimpleAclAuthorizer
security.inter.broker.protocol=SASL_PLAINTEXT
sasl.mechanism.inter.broker.protocol=PLAINTEXT
sasl.enabled.mechanisms=PLAINTEXT

Zookeeper properties:

authProvider.1=org.apache.zookeeper.server.auth.SASLAuthenticationProvider
requireClientAuthScheme=sasl
jaasLoginRenew=3600000

When I try to start Kafka server I am continuously getting this error.

[2019-04-03 16:32:31,267] DEBUG Accepted connection from
/127.0.0.1:45794 on /127.0.0.1:9092 and assigned it to processor 1,
sendBufferSize [actual|requested]: [102400|102400] recvBufferSize
[actual|requested]: [102400|102400] (kafka.network.Acceptor)
[2019-04-03 16:32:31,267] DEBUG Processor 1 listening to new
connection from /127.0.0.1:45794 (kafka.network.Processor)
[2019-04-03 16:32:31,268] WARN [Controller id=0, targetBrokerId=0]
Unexpected error from localhost/127.0.0.1; closing connection
(org.apache.kafka.common.network.Selector)
java.lang.NullPointerException
    at 
org.apache.kafka.common.security.authenticator.SaslClientAuthenticator.sendSaslClientToken(SaslClientAuthenticator.java:266)
    at 
org.apache.kafka.common.security.authenticator.SaslClientAuthenticator.authenticate(SaslClientAuthenticator.java:204)
    at 
org.apache.kafka.common.network.KafkaChannel.prepare(KafkaChannel.java:141)
    at 
org.apache.kafka.common.network.Selector.pollSelectionKeys(Selector.java:532)
    at org.apache.kafka.common.network.Selector.poll(Selector.java:467)
    at org.apache.kafka.clients.NetworkClient.poll(NetworkClient.java:535)
    at 
org.apache.kafka.clients.NetworkClientUtils.awaitReady(NetworkClientUtils.java:74)
    at 
kafka.controller.RequestSendThread.brokerReady(ControllerChannelManager.scala:279)
    at 
kafka.controller.RequestSendThread.doWork(ControllerChannelManager.scala:233)
    at kafka.utils.ShutdownableThread.run(ShutdownableThread.scala:82)
[2019-04-03 16:32:31,268] WARN [Controller id=0, targetBrokerId=0]
Connection to node 0 (localhost/127.0.0.1:9092) terminated during
authentication. This may indicate that authentication failed due to
invalid credentials. (org.apache.kafka.clients.NetworkClient)

Please help. Unable to understand this problem.


Thanks & Regards,

Shantanu Deshmukh