Error: redis replication id mismatch

What's Causing This Error

The error message 'redis replication id mismatch' typically indicates that there is a disagreement or conflict between the replication IDs. Replication ID is a unique identifier assigned to each master node in the Redis setup.

When Redis sets up a replication, it creates a new replication ID for the master and backup IDs for the old data set. If a slave disconnects and tries to reconnect after the master has already switched to a new replication ID, the slave might still use an old replication ID. This can cause the reported 'replication id mismatch' error.

This error can also be due to network interruptions, incorrect configuration of the Redis instances, or sudden crashes that disrupt the normal synchronization process.

Solution - Here's How To Resolve It

To resolve this issue, you may need to follow these steps:

1. Check Configuration: Make sure your Redis instances are correctly configured. Ensure that the master and slave instances have proper and matching configurations.

2. Resync Instances: Try to force a resynchronization of your instances. You can do this by using the SLAVEOF NO ONE command on the slave, and then reestablishing the slave connection with the SLAVEOF command.

3. Inspect Network: Check for any network issues that could be interfering with the connection between the master and slave instances. Fix these before trying a resync.

4. Data Persistence: Enable data persistence such as RDB or AOF to ensure that your data survives even if the instance is restarted.

5. Upgrade Redis Version: If you are running an outdated version of Redis, consider upgrading to the latest stable release. Some older versions may contain bugs related to replication which have been fixed in later versions.