Why can't I connect to Kafka/Zookeeper? (In a Docker) - apache-kafka

Question

I'm running Kafka (0.10.0.0) in a Docker on a Mac (w/docker-machine). I derived my Dockerfile from Spotify's, which means Kafka and Zookeeper run in the same image.
My instance starts cleanly and poking around inside it appears everything is normal/OK.
Docker maps ports 2181 and 9092 to high-ports 32822 and 32820 in this case. From outside my running Kafka Docker I am able to successfully telnet 192.168.99.100 32822 (where 192.168.99.100 is the IP of my docker-machine). From there I can issue a zookeeper command and get expected output.
It all seems so encouraging, but... I then try this code:
val numPartitions = 4
val replicationFactor = 1
val topicConfig = new java.util.Properties
// zookeeper = "192.168.99.100:32822"
val zkClient = ZkUtils(zookeeper, 10000, 10000, false)
try {
AdminUtils.createTopic(zkClient, topic, numPartitions, replicationFactor, topicConfig)
} catch {
case k: kafka.common.TopicExistsException => // do nothing...topic exists
}
zkClient.close()
This produces this error output:
DEBUG ZkConnection - Creating new ZookKeeper instance to connect to 192.168.99.100:32822.
INFO ZkEventThread - Starting ZkClient event thread.
INFO ZooKeeper - Client environment:zookeeper.version=3.4.6-1569965, built on 02/20/2014 09:09 GMT
INFO ZooKeeper - Client environment:host.name=172.25.42.82
INFO ZooKeeper - Client environment:java.version=1.8.0_60
INFO ZooKeeper - Client environment:java.vendor=Oracle Corporation
INFO ZooKeeper - Client environment:java.home=/Library/Java/JavaVirtualMachines/jdk1.8.0_60.jdk/Contents/Home/jre
INFO ZooKeeper - Client environment:java.class.path=/usr/local/Cellar/sbt/0.13.11/libexec/sbt-launch.jar
INFO ZooKeeper - Client environment:java.library.path=/Users/wmy965/Library/Java/Extensions:/Library/Java/Extensions:/Network/Library/Java/Extensions:/System/Library/Java/Extensions:/usr/lib/java:.
INFO ZooKeeper - Client environment:java.io.tmpdir=/var/folders/ph/ccz4n1qs62n0bn8mqdg94gswt1jlwk/T/
INFO ZooKeeper - Client environment:java.compiler=<NA>
INFO ZooKeeper - Client environment:os.name=Mac OS X
INFO ZooKeeper - Client environment:os.arch=x86_64
INFO ZooKeeper - Client environment:os.version=10.11.5
INFO ZooKeeper - Client environment:user.name=wmy965
INFO ZooKeeper - Client environment:user.home=/Users/wmy965
INFO ZooKeeper - Client environment:user.dir=/Users/wmy965/git/LateKafka
INFO ZooKeeper - Initiating client connection, connectString=192.168.99.100:32822 sessionTimeout=10000 watcher=org.I0Itec.zkclient.ZkClient#55397e3
DEBUG ClientCnxn - zookeeper.disableAutoWatchReset is false
DEBUG ZkClient - Awaiting connection to Zookeeper server
INFO ZkClient - Waiting for keeper state SyncConnected
INFO ClientCnxn - Opening socket connection to server 192.168.99.100/192.168.99.100:32822. Will not attempt to authenticate using SASL (unknown error)
WARN ClientCnxn - Session 0x0 for server null, unexpected error, closing socket connection and attempting reconnect
java.net.ConnectException: Connection refused
at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method)
at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:717)
at org.apache.zookeeper.ClientCnxnSocketNIO.doTransport(ClientCnxnSocketNIO.java:361)
at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1081)
DEBUG ClientCnxnSocketNIO - Ignoring exception during shutdown input
java.nio.channels.ClosedChannelException
at sun.nio.ch.SocketChannelImpl.shutdownInput(SocketChannelImpl.java:780)
at sun.nio.ch.SocketAdaptor.shutdownInput(SocketAdaptor.java:399)
at org.apache.zookeeper.ClientCnxnSocketNIO.cleanup(ClientCnxnSocketNIO.java:200)
at org.apache.zookeeper.ClientCnxn$SendThread.cleanup(ClientCnxn.java:1185)
at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1110)
DEBUG ClientCnxnSocketNIO - Ignoring exception during shutdown output
java.nio.channels.ClosedChannelException
at sun.nio.ch.SocketChannelImpl.shutdownOutput(SocketChannelImpl.java:797)
at sun.nio.ch.SocketAdaptor.shutdownOutput(SocketAdaptor.java:407)
at org.apache.zookeeper.ClientCnxnSocketNIO.cleanup(ClientCnxnSocketNIO.java:207)
at org.apache.zookeeper.ClientCnxn$SendThread.cleanup(ClientCnxn.java:1185)
at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1110)
INFO ClientCnxn - Opening socket connection to server 192.168.99.100/192.168.99.100:32822. Will not attempt to authenticate using SASL (unknown error)
INFO ClientCnxn - Socket connection established to 192.168.99.100/192.168.99.100:32822, initiating session
DEBUG ClientCnxn - Session establishment request sent on 192.168.99.100/192.168.99.100:32822
INFO ClientCnxn - Session establishment complete on server 192.168.99.100/192.168.99.100:32822, sessionid = 0x155225c51720000, negotiated timeout = 10000
DEBUG ZkClient - Received event: WatchedEvent state:SyncConnected type:None path:null
INFO ZkClient - zookeeper state changed (SyncConnected)
DEBUG ZkClient - Leaving process event
DEBUG ZkClient - State is SyncConnected
DEBUG ClientCnxn - Reading reply sessionid:0x155225c51720000, packet:: clientPath:null serverPath:null finished:false header:: 1,8 replyHeader:: 1,1,-101 request:: '/brokers/ids,F response:: v{}
It looks like I can't connect (presumably to zookeeper). Why not?

Answer 1

In new kafka streams, the ip of producer must have been knowing by kafka (docker). Kafka send their uuid (you can show this in /etc/hosts inside kafka docker) and espect response from this.
Summary:
Map uuid kafka docker to docker-machine in /etc/host of mac OS.
To help you, how to change etc/host file in mac:
https://www.tekrevue.com/tip/edit-hosts-file-mac-os-x/

Answer 2

Cleaner would be to set advertised.listeners=host-ip:port since advertised.host.name and advertised.port are deprecated in Kafka server.properties file.
If set host-ip to 0.0.0.0 it will listen requests from anywhere. But it's insecure.