Kafka Migration Tests

Kafka migration strategy tests

Running

Start stack:

docker-compose up -d

Run some producers:

docker-compose exec mirror kafka-verifiable-producer.sh --broker-list kafkaA1:9092 --throughput 1 --topic TestTopic

Run some consumers:

docker-compose exec mirror kafka-console-consumer.sh --bootstrap-server kafkaA1:9092 --group=test --topic TestTopic

Debezium

To login in to mysql use

docker-compose exec mysql sh -c 'mysql -umysqluser -p'

Start the connector

curl -i -X POST -H "Accept:application/json" -H  "Content-Type:application/json" http://localhost:8083/connectors/ -d @register-mysql.json

Update the connector

curl -i -X PUT -H "Accept:application/json"  -H  "Content-Type:application/json" http://localhost:8083/connectors/inventory-connector/config/ -d @update-mysql.json

After updating the connector I was able to update Debezium's configuration pointing to the new cluster. Debezium did not loose its configuration.

Mirror Maker 2.0

Launch with: connect-mirror-maker.sh mm2.properties

Migrating consumers

• Most (if not all) consumers have offset reset set to latest. Mostly because of issues for re-consuming a topic without having idempotency on the consumers.

• Ideal strategy would be transfer the offset to the new cluster: this seams to be possible with confluences' replicator, but the license only allows to use it for 30 days.

• The other strategy would be migrating with downtime, this requires mapping the producer/consumer graph.

• Proposal migrate critical flows consumers beforehand using replication. Mass migrate the other flows updating the DNS and roll restarting the services.

Kafka Proxy Tests

Run the producer through the proxy and put consumers on the two kafka cluster to see how a fallback the the new cluster would affect the producers.

docker-compose exec kafka1 kafka-verifiable-producer.sh --broker-list proxy:9092 --throughput 1 --topic TestTopic

It's not a good idea to use proxy to change producers/consumers to a new cluster. Consumers loose tracking of their group, producer might try to produce to the wrong broker.

MirroMaker 2.0 group offset sync

This PR implements que group offset sync between clusters. But if does not create consumer groups in the target cluster.

kafka-consumer-groups.sh --bootstrap-server kafkaA1:9092 --list > groups1.txt & kafka-consumer-groups.sh --bootstrap-server kafkaB1:9092 --list > groups2.txt
comm -23 groups1.txt groups2.txt
kafka-consumer-groups.sh --bootstrap-server kafkaA1:9092 --group testx --reset-offsets --to-current --topic TestTopic --execute

Doesn't work: Testing metadata isn't updated, so you need to restart mirror maker 2.0 to update topics and consumer groups.