Kafka-Connect: Creating a new connector in distributed mode is creating new group

I think some clarification is required...

1. group.id in the worker.properties file does not refer to consumer groups. It is a "worker group" - multiple workers in the same worker group will split work between them - so if the same connector has many tasks (for example the JDBC connector has a task for every table), those tasks will be allocated to all workers in the group.

2. Sink connectors do have consumers that are part of a consumer group. The group.id of this group is always "connect-"+connector name. In your case, you got "connect-connector1" and "connect-connector2" based on your connector names. This also means that the only way two connectors will be in the same group is... if they have the same name. But names are unique, so you can't have two connectors in the same group. The reason is...

3. Connectors don't really get events themselves, they just start a bunch of tasks. Each of the tasks has consumers that are part of the connector consumer group and each task will handle a subset of the topics and partitions independently. So having two connectors in the same group, basically means that all their tasks are part of the same group - so why do you need two connectors? Just configure more topics and more tasks for that one connector and you are all set.

The only exception is if the connector you are using doesn't use tasks correctly or limits you to just one task. In that case - either they have a good reason or (more likely) someone needs to improve their connector...