Trouble connecting to MSK over SSL using Kafka-Connect - apache-kafka

Question

I'm having trouble using the AWS MSK TLS endpoints in Confluent Kafka-Connect image as it times out creating/reading to the topics. Works totally fine when I pass the PlainText endpoints.
I tried referencing the jks store path available on the that docker image still doesn't work not quite sure if I'm missing any other configs. From what I read from AWS docs Amazon MSK brokers use public AWS Certificate Manager certificates therefore, any truststore that trusts Amazon Trust Services also trusts the certificates of Amazon MSK brokers.
**Error:**
org.apache.kafka.connect.errors.ConnectException: Timed out while checking for or creating topic(s) '_confluent-command'. This could indicate a connectivity issue, unavailable topic partitions, or if this is your first use of the topic it may have taken too long to create.
Attaching the kafka-connect config I'm using any help would be great :)
INFO org.apache.kafka.clients.admin.AdminClientConfig - AdminClientConfig values:
bootstrap.servers = [**.us-east-1.amazonaws.com:9094,*.us-east-1.amazonaws.com:9094]
client.dns.lookup = default
client.id =
connections.max.idle.ms = 300000
metadata.max.age.ms = 300000
metric.reporters = []
metrics.num.samples = 2
metrics.recording.level = INFO
metrics.sample.window.ms = 30000
receive.buffer.bytes = 65536
reconnect.backoff.max.ms = 1000
reconnect.backoff.ms = 50
request.timeout.ms = 120000
retries = 5
retry.backoff.ms = 100
sasl.client.callback.handler.class = null
sasl.jaas.config = null
sasl.kerberos.kinit.cmd = /usr/bin/kinit
sasl.kerberos.min.time.before.relogin = 60000
sasl.kerberos.service.name = null
sasl.kerberos.ticket.renew.jitter = 0.05
sasl.kerberos.ticket.renew.window.factor = 0.8
sasl.login.callback.handler.class = null
sasl.login.class = null
sasl.login.refresh.buffer.seconds = 300
sasl.login.refresh.min.period.seconds = 60
sasl.login.refresh.window.factor = 0.8
sasl.login.refresh.window.jitter = 0.05
sasl.mechanism = GSSAPI
security.protocol = SSL
security.providers = null
send.buffer.bytes = 131072
ssl.cipher.suites = null
ssl.enabled.protocols = [TLSv1.2, TLSv1.1, TLSv1]
ssl.endpoint.identification.algorithm = https
ssl.key.password = null
ssl.keymanager.algorithm = SunX509
ssl.keystore.location = null
ssl.keystore.password = null
ssl.keystore.type = JKS
ssl.protocol = TLS
ssl.provider = null
ssl.secure.random.implementation = null
ssl.trustmanager.algorithm = PKIX
ssl.truststore.location = JKSStorePath
ssl.truststore.password = ***
ssl.truststore.type = JKS

Answer 1

I used the java cacerts in the docker image at /usr/lib/jvm/zulu-8-amd64/jre/lib/security/cacerts as the truststore. With keytool, if you look at the certs:
keytool --list -v -keystore /usr/lib/jvm/zulu-8-amd64/jre/lib/security/cacerts|grep Amazon
It will list out the Amazon CAs.
I then started the container using:
docker run -d \
--name=kafka-connect-avro-ssl \
--net=host \
-e CONNECT_BOOTSTRAP_SERVERS=<msk_broker1>:9094,<msk_broker2>:9094,<msk_broker3>:9094 \
-e CONNECT_REST_PORT=28083 \
-e CONNECT_GROUP_ID="quickstart-avro" \
-e CONNECT_CONFIG_STORAGE_TOPIC="avro-config" \
-e CONNECT_OFFSET_STORAGE_TOPIC="avro-offsets" \
-e CONNECT_STATUS_STORAGE_TOPIC="avro-status" \
-e CONNECT_KEY_CONVERTER="io.confluent.connect.avro.AvroConverter" \
-e CONNECT_VALUE_CONVERTER="io.confluent.connect.avro.AvroConverter" \
-e CONNECT_KEY_CONVERTER_SCHEMA_REGISTRY_URL="<hostname of EC2 instance>:8081" \
-e CONNECT_VALUE_CONVERTER_SCHEMA_REGISTRY_URL="http://<hostname of EC2 instance>:8081" \
-e CONNECT_INTERNAL_KEY_CONVERTER="org.apache.kafka.connect.json.JsonConverter" \
-e CONNECT_INTERNAL_VALUE_CONVERTER="org.apache.kafka.connect.json.JsonConverter" \
-e CONNECT_REST_ADVERTISED_HOST_NAME="<hostname of EC2 instance>" \
-e CONNECT_LOG4J_ROOT_LOGLEVEL=DEBUG \
-e CONNECT_SECURITY_PROTOCOL=SSL \
-e CONNECT_SSL_TRUSTSTORE_LOCATION=/usr/lib/jvm/zulu-8-amd64/jre/lib/security/cacerts \
-e CONNECT_SSL_TRUSTSTORE_PASSWORD=changeit \
confluentinc/cp-kafka-connect:latest
With that, it started successfully. I was also able to connect to the container, create topics, produce and consume from within the container. If you're unable to create topics, it could be a network connectivity issue, possibly a security group issue of the security group attached to the MSK cluster, blocking ports 2181 and TLS port 9094.