Can't start zookeeper - apache-kafka

Question

I'm using confluent platform, the zookeeper is active with status lookup. but when I try to start kafka with confluent it shows zookeeper is down.
$ sudo service zookeeper status
Redirecting to /bin/systemctl status zookeeper.service
● zookeeper.service - Zookeeper
Loaded: loaded (/etc/systemd/system/zookeeper.service; disabled; vendor preset: disabled)
Active: active (running) since Tue 2017-08-08 17:25:34 PDT; 16h ago
Docs: http://kafka.apache.org/documentation.html
Process: 3774 ExecStop=/var/www/confluent/bin/zookeeper-server-stop (code=exited, status=1/FAILURE)
Main PID: 3785 (java)
CGroup: /system.slice/zookeeper.service
└─3785 java -Xmx512M -Xms512M -server -XX:+UseG1GC -XX:MaxGCPauseMillis=20 -XX:InitiatingHeapOccupancyPercent=35 -XX:+DisableExplicitGC -Djava.awt.headless=true -Xloggc:/var/log...
zookeeper[3785]: [2017-08-08 17:26:09,005] INFO Processed session termination for sessionid: 0x15dc460fd0c0000 (org.apache.zooke...Processor)
zookeeper[3785]: [2017-08-08 17:26:39,000] INFO Expiring session 0x15dc4364baf0004, timeout of 60000ms exceeded (org.apache.zook...perServer)
zookeeper[3785]: [2017-08-08 17:26:39,000] INFO Expiring session 0x15dc4364baf0002, timeout of 60000ms exceeded (org.apache.zook...perServer)
zookeeper[3785]: [2017-08-08 17:26:39,000] INFO Expiring session 0x15dc4364baf0003, timeout of 60000ms exceeded (org.apache.zook...perServer)
zookeeper[3785]: [2017-08-08 17:26:39,001] INFO Processed session termination for sessionid: 0x15dc4364baf0004 (org.apache.zooke...Processor)
zookeeper[3785]: [2017-08-08 17:26:39,002] INFO Processed session termination for sessionid: 0x15dc4364baf0002 (org.apache.zooke...Processor)
zookeeper[3785]: [2017-08-08 17:26:39,002] INFO Processed session termination for sessionid: 0x15dc4364baf0003 (org.apache.zooke...Processor)
zookeeper[3785]: [2017-08-09 09:56:26,711] INFO Accepted socket connection from /127.0.0.1:46446 (org.apache.zookeeper.server.NI...xnFactory)
zookeeper[3785]: [2017-08-09 09:59:14,796] WARN Exception causing close of session 0x0 due to java.io.IOException: Len error -72...erverCnxn)
zookeeper[3785]: [2017-08-09 09:59:14,796] INFO Closed socket connection for client /127.0.0.1:46446 (no session established for...erverCnxn)
Hint: Some lines were ellipsized, use -l to show in full.
$ confluent start kafka
Starting zookeeper
|Zookeeper failed to start
zookeeper is [DOWN]
Cannot start Kafka, Zookeeper is not running. Check your deployment

Answer 1

This is because zookeeper is already running, you can check the process with
ps aux|grep zookeeper
and kill the process manually and it is gonna work.

Answer 2

The most common cause for the message you are seeing when running:
confluent start kafka
and informs you that zookeeper is down, is that there's another zookeeper instance that is currently running, and the new zookeeper instance can not bind to its required port (by default this port is 2181).
A few options at your disposal to figure out what's the other zookeeper instance that is currently running when you try to issue confluent start kafka are:
run jps to see the running java processes. Zookeeper is the process named QuorumPeerMain next to its process ID. (equivalent to running ps xuaww | grep -i zookeeper or equivalent).
run lsof -i :2181 to figure out what the process that is running and has reserved the default zookeeper port (in this example 2181, but might be different in your system).
Try running confluent start kafka again after stopping the above process.

Answer 3

I received the same message. In my case I didn't set $JAVA_HOME variable properly.

Answer 4

You are mixing two installations.
confluent start kafka would depend on you running confluent start zookeeper.
Rather, it seems you already have systemctl running Zookeeper, so you should ideally just configure your server.properties and use the regular kafka-server-start script. And/or create a systemctl file for Kafka.

Answer 5

run $ confluent log zookeeper you will be able to see the log for any errors
there is high chance zookeeper is already running and using the port 2181,
use $ sudo lsof -i :1-2181 to see which process is using that port and try to kill and try again or
run $ sudo netstat -plten | grep java to see processes and ports they are on.
run kill -9 <pid> to kill the process.