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Question:

How do I setup watcher to watch a Kafka-Connect stream in real-time as changes are made to the database? I am getting Error while fetching metadata with correlation id 2 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE}. What is causing the problem and how do I fix it?

Context:

This question is related to: Debezium How do I correctly register the SqlServer connector with Kafka Connect - connection refused and https://github.com/debezium/debezium-examples/blob/master/tutorial/README.md#using-sql-server

In Windows 10, I have setup Zookeeper, Kafka, and Kafka-Connector all in their own separate Docker containers using the following commands:

docker run -it --rm --name zookeeper -p 2181:2181 -p 2888:2888 -p 3888:3888 debezium/zookeeper:1.1
docker run -it --rm --name kafka -p 9092:9092 -e KAFKA_ADVERTISED_HOST_NAME: kafka --link zookeeper:zookeeper debezium/kafka:1.1
docker run -it --rm --name connect -p 8083:8083 -e GROUP_ID=1 -e CONFIG_STORAGE_TOPIC=my_connect_configs -e OFFSET_STORAGE_TOPIC=my_connect_offsets -e STATUS_STORAGE_TOPIC=my_connect_statuses --link zookeeper:zookeeper --link kafka:kafka debezium/connect:1.1

I then setup a Kafka Connector to an instance of SQL Server that is running on the localhost, outside of a Docker container. The logs show that the connector can connect to the database and grab the CDC data. Up until this point I am OK.

However, when I try to create a watcher, using the following command:

docker run -it --rm --name watcher --link zookeeper:zookeeper --link kafka:kafka debezium/kafka:1.1

I get the following error. 

watch-topic -a -k dbhistory.Test.Posts
WARNING: Using default BROKER_ID=1, which is valid only for non-clustered installations.
Using ZOOKEEPER_CONNECT=172.17.0.2:2181
Using KAFKA_ADVERTISED_LISTENERS=PLAINTEXT://172.17.0.5:9092
Using KAFKA_BROKER=172.17.0.3:9092
Contents of topic dbhistory.Test.Posts:
[2020-04-08 15:18:39,373] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 2 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:41:20,501] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Connection to node 1 (/172.17.0.3:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:41:20,605] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Connection to node 1 (/172.17.0.3:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:41:20,807] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Connection to node 1 (/172.17.0.3:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:41:21,262] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Connection to node 1 (/172.17.0.3:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:41:22,120] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Connection to node 1 (/172.17.0.3:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:41:23,330] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Connection to node 1 (/172.17.0.3:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:41:24,189] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Connection to node 1 (/172.17.0.3:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:41:59,826] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Connection to node 1 (/172.17.0.3:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:04,051] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Connection to node 1 (/172.17.0.3:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:07,121] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Connection to node 1 (/172.17.0.3:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:08,024] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Connection to node 1 (/172.17.0.3:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:09,354] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 11570 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:09,458] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 11572 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:09,571] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 11574 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:09,677] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 11576 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:09,786] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 11578 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:09,895] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 11580 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:10,002] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 11582 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:10,112] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 11584 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:10,220] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 11586 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:10,326] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 11588 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:10,435] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 11590 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:10,537] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 11592 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:10,648] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 11594 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:10,751] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 11596 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 16:42:10,854] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Error while fetching metadata with correlation id 11598 : {dbhistory.Test.Posts=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient)
[2020-04-08 17:08:48,268] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Connection to node 1 (/172.17.0.3:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
[2020-04-08 17:09:55,602] WARN [Consumer clientId=consumer-console-consumer-3848-1, groupId=console-consumer-3848] Connection to node 1 (/172.17.0.3:9092) could not be established. Broker may not be available. (org.apache.kafka.clients.NetworkClient)
J Weezy
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  • Hi, these two lines are in clear cotradiction ``` Using KAFKA_ADVERTISED_LISTENERS=PLAINTEXT://172.17.0.5:9092 Using KAFKA_BROKER=172.17.0.3:9092 ``` The IP should be the same in both cases. What is IP of the KAfka container? Also is `-e KAFKA_ADVERTISED_HOST_NAME: kafka` the correct format? I am usually using equal sign when setting env vars – Jiri Pechanec Apr 14 '20 at 05:07
  • @JiriPechanec I see that in the error, but how do I fix it? Please note that I am using the default values provided to me on the help site. My assumption is that they should work out of the box. – J Weezy Apr 14 '20 at 05:09
  • Do you have the option of using Docker Compose? It will make your life a *lot* easier. I can provide an answer based on Docker Compose if this would be acceptable. – Robin Moffatt Apr 14 '20 at 16:24
  • Yes. For a Proof of Concept. Right now I am setting it up to run in Docker. The requirement is that Debezium must connect to an instance of SQL Server that is on the machine and not in a Docker Container. Ultimately, it will run outside of Docker. – J Weezy Apr 15 '20 at 02:48

2 Answers2

1

Can you try once adding --network=host in the docker run.

Naveen Kulkarni
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  • I am no longer on this project, so I have not way of testing to confirm if this is the answer. None the less, I have upvoted it. Thank you. – J Weezy Dec 16 '22 at 19:55
0

The issue is most likely caused by the way you defined your environment variable.

Replace:

-e KAFKA_ADVERTISED_HOST_NAME: kafka

with:

-e KAFKA_ADVERTISED_HOST_NAME=kafka
senjin.hajrulahovic
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  • I am no longer on this project, so I have not way of testing to confirm if this is the answer. None the less, I have upvoted it. Thank you. – J Weezy Apr 05 '21 at 15:24