# Troubleshooting cross-Region replicas for Amazon Aurora MySQL
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 Following you can find a list of common error messages that you might encounter when creating an Amazon Aurora cross-Region read replica, and how to resolve the specified errors. 

## Source cluster [DB cluster ARN] doesn't have binlogs enabled
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 To resolve this issue, turn on binary logging on the source DB cluster. For more information, see [Before you begin](AuroraMySQL.Replication.CrossRegion.md#AuroraMySQL.Replication.CrossRegion.Prerequisites). 

## Source cluster [DB cluster ARN] doesn't have cluster parameter group in sync on writer
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 You receive this error if you have updated the `binlog_format` DB cluster parameter, but have not rebooted the primary instance for the DB cluster. Reboot the primary instance (that is, the writer) for the DB cluster and try again. 

## Source cluster [DB cluster ARN] already has a read replica in this region
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 You can have up to five cross-Region DB clusters that are read replicas for each source DB cluster in any AWS Region. If you already have the maximum number of read replicas for a DB cluster in a particular AWS Region, you must delete an existing one before you can create a new cross-Region DB cluster in that Region. 

## DB cluster [DB cluster ARN] requires a database engine upgrade for cross-Region replication support
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 To resolve this issue, upgrade the database engine version for all of the instances in the source DB cluster to the most recent database engine version, and then try creating a cross-Region read replica DB again.