If your environment uses MirrorMaker 2 for geo-replication across multiple Event Streams clusters, migrate each cluster to Confluent Platform individually first. After all relevant clusters are migrated, replace MirrorMaker 2 with Cluster Linking between the Confluent Platform clusters. Keep MirrorMaker 2 running until each cluster is fully migrated and validated.
Choosing a replication method
The following table explains the replication methods available in MirrorMaker 2 and Confluent:
| Existing MirrorMaker 2 setup | Confluent approach | Notes |
|---|---|---|
| Geo-replication across multiple clusters for geographic redundancy or disaster recovery | Cluster Linking between Confluent Platform clusters | Set up after all relevant clusters are migrated to Confluent Platform. Preserves message bytes and offsets without a separate worker deployment. |
| Replication where Cluster Linking cannot be used (for example, network restrictions prevent broker-to-broker connectivity, or topics must be renamed) | Confluent Replicator | Runs as a Kafka Connect worker and requires only client-level network access to the source cluster. For consumer offset handling requirements, see geo-replication offsets. |
Migrating replication flows
Migrate the replication flows as follows:
- List each MirrorMaker 2 replication flow, including the source cluster, target cluster, topic include and exclude lists, and replication policy.
- Decide whether to use Cluster Linking or Confluent Replicator based on your network connectivity, and whether topics need to be renamed or schema subjects need to change.
- Note the difference in how topic names are handled. MirrorMaker 2 prefixes replicated topic names with the source cluster alias by default, for example
source-cluster.orders. Cluster Linking keeps the original topic name, for exampleorders. If your applications depend on the prefixed topic names, update them or use Confluent Replicator to reproduce the same naming pattern. - Set up replication on Confluent Platform by using Cluster Linking or Confluent Replicator.
- Verify that the replication lag is zero for all topics.
Keep MirrorMaker 2 running until all applications are migrated and validated. Remove the MirrorMaker 2 deployment as part of decommissioning Event Streams.