How to check if zookeeper and kafka are running correctly

Check on zookeeper:

telnet ipaddress port
stats

For example:

telnet 172.16.21.3 2181
Trying 172.16.21.3...
Connected to 172.16.21.3.
Escape character is '^]'.
stats
Zookeeper version: 3.4.9-1757313, built on 08/23/2016 06:50 GMT
Clients:
 /172.16.21.4:58476[1](queued=0,recved=321,sent=327)
 /172.16.38.0:55630[1](queued=0,recved=245,sent=245)
 /172.16.39.0:38124[1](queued=0,recved=240,sent=240)
 /172.16.21.1:39190[0](queued=0,recved=1,sent=0)

Latency min/avg/max: 0/0/14
Received: 807
Sent: 812
Connections: 4
Outstanding: 0
Zxid: 0x100000033
Mode: leader
Node count: 31
Connection closed by foreign host.

To check if the kafka nodes actually all registered, do the following:

1. docker exec -it zookeeper1st bash
2. cd /zookeeper-3.4.9/bin/zkCli.sh  ls /brokers/ids

WatchedEvent state:SyncConnected type:None path:null
[1, 2, 3]

or

1. docker exec -it kafka3rd bash
2. ./kafka-topics.sh --list --zookeeper zookeeper1st:2181
3. ./kafka-topics.sh --describe --zookeeper zookeeper1st:2181