I am trying to connect Kafka Java Client to a Kafka broker using SASL Plain. But when I try to send a message from the Producer, the Kafka Server logs the following error:
[2020-04-30 14:48:14,955] INFO [SocketServer brokerId=0] Failed authentication with /127.0.0.1 (Unexpected Kafka request of type METADATA during SASL handshake.) (org.apache.kafka.common.network.Selector)
By the looks, the producer tries to send a metadata request, before the SASL handshake. How can I do the handshake before sending the message?
Following is my kafka_server_jaas.conf
file, which is used for Kafka Server.
KafkaServer {
org.apache.kafka.common.security.plain.PlainLoginModule required
username="admin"
password="admin-secret"
user_admin="admin-secret";
};
Client {
org.apache.kafka.common.security.plain.PlainLoginModule required
username="admin"
password="admin-secret";
};
Following is my zookeeper_jaas.conf
file, which is used for the zookeeper:
Server {
org.apache.kafka.common.security.plain.PlainLoginModule required
username="admin"
password="admin-secret"
user_admin="admin-secret";
};
In my Java producer, I set the following properties:
Properties properties = new Properties();
properties.put("bootstrap.servers", "localhost:9092");
properties.put("sasl.jaas.config", "org.apache.kafka.common.security.plain.PlainLoginModule required username=\"admin\" password=\"admin_secret\"");
properties.put("sasl.mechanisms", "PLAIN");
properties.put("value.serializer", "org.apache.kafka.common.serialization.StringSerializer");
KafkaProducer kafkaProducer = new KafkaProducer(properties);
Is there anything wrong I am doing?
You need to specify security.protocol
, otherwise by default, Kafka clients do not use SASL
.
In your client properties, add:
properties.put("security.protocol", "SASL_SSL");
There's also SASL_PLAINTEXT
but it's not recommended to use the PLAIN
mechanism over SASL_PLAINTEXT
as effectively the password will be exchanged in cleartext.