How do I resolve issues with an Amazon RDS database that is in an incompatible-network state?

Short description

An incompatible-network state indicates one or more of the following is true of the Amazon RDS DB instance:

• There are no available IP addresses in the subnet that the Amazon RDS DB instance was launched into.
• The subnet mentioned in the Amazon RDS DB subnet group no longer exists in the Amazon Virtual Private Cloud (Amazon VPC).
• The RDS DB instance is publicly accessible, but the DNS hostnames and the DNS resolution options are turned off. Both options must be turned on for an RDS DB instance to be publicly accessible.
• You reached your service quota for elastic network interfaces in the AWS Region that you're using, and you must request a service quota increase.
• The original elastic network interface of the RDS DB instance was deleted while the instance was stopped. When the RDS DB instance was restarted, the elastic network interface wasn't found.

The incompatible-network state of your RDS DB instance could be the result of performing one of the following actions:

• Modifying the RDS DB instance's class.
• Modifying the RDS DB instance to use a Multi-AZ deployment.
• Replacing a host due to a maintenance event.
• Launching a replacement RDS DB instance.
• Creating a new RDS DB instance after the quota for the elastic network interfaces has been reached.
• Restoring from a snapshot backup.
• Starting an RDS DB instance that was stopped.

For more details about why your RDS DB instance is in an incompatible-network state, see Viewing Amazon RDS events.

Resolution

The incompatible-network state means that the Amazon RDS DB instance might still be accessible at the database level, but you can't modify or reboot it. It's a best practice to have a backup (snapshot or logical), in case your RDS DB instance enters an incompatible-network state. Having a backup allows you to restore the data to another RDS DB instance.

1. Open the Amazon RDS console, and then choose Databases from the navigation pane.
2. Choose the RDS DB instance that is in an incompatible-network state, and then note the VPC ID and subnet IDs from the Connectivity & Security pane.
3. Open the Amazon VPC console, and then choose Your VPCs from the navigation pane.
4. Select the VPC that you noted previously, choose Actions, and then choose Edit DNS hostnames. If DNS hostnames is not turned on, then check the box for enable.
5. From Your VPCs, select the VPC that you noted previously, choose Actions, and then choose Edit DNS resolution. If the DNS resolution is not turned on, then check the box for enable.
6. Choose Subnets from the navigation pane. Confirm that all subnets noted previously from the RDS DB instance details section are listed and have available IP addresses.
7. Open the Amazon Elastic Compute Cloud (Amazon EC2) console, and then confirm that you haven't reached the quota for elastic network interfaces. Request a service quota increase if needed.
   Note: For more information on quotas for network interfaces per AWS Region, see Network interfaces.

Note: Your instance will be in the incompatible-network state if RDS can't allocate your IP address under the following circumstances:

1. You're using Amazon RDS on AWS Outposts.
2. You activate the Customer-owned IP (CoIP) address setting.

To fix an RDS DB instance that's in an incompatible-network state, verify if you've turned on automated backups for your RDS DB instance. If you did turn on automated backups, then temporarily stop any writes to the database and perform a point-in-time recovery (PITR).

If you didn't turn on automated backups, create a new RDS DB instance. Then, migrate the data using AWS Database Migration Service (AWS DMS), or by using a backup and restore tool. For example, mysqldump, pg_dump, expdp / impdp.

Important: After an instance enters an incompatible-network state, the RDS DB instance might not be accessible at the DB level to perform a logical backup.

Related information

DB instance status

Working with an Amazon RDS DB Instance in a VPC

My Amazon RDS instance status is stuck in an incompatible-parameters state. How can I fix this?