How do I resolve an "insufficient free IP addresses in subnets" error when I create an Amazon Redshift Serverless workgroup?

Short description

When you create an Amazon Redshift Serverless workgroup and there aren't enough free IP addresses in subnets, you get the following error message: "Error: Insufficient free IP addresses found in subnets".

The error message occurs because of one or more of the following reasons:

• Your subnets contain too many resources, which leaves insufficient IP addresses for your new Amazon Redshift Serverless cluster.
• Your Amazon Virtual Private Cloud (Amazon VPC) has a limited IP address range and the existing subnets have exhausted most of the available IP addresses.
• Your subnet configuration doesn't meet the Amazon Redshift Serverless requirement of at least 3 subnets in different Availability Zones.

Amazon Redshift Serverless clusters require subnets with sufficient IP addresses. To create an Amazon Redshift Serverless workgroup, you must specify an Amazon VPC, security groups, and at least 3 subnets in different Availability Zones.

Resolution

Troubleshoot IP address availability issues

Note: If you receive errors when you run AWS Command Line Interface (AWS CLI) commands, then see Troubleshooting errors for the AWS CLI. Also, make sure that you're using the most recent AWS CLI version.

To resolve IP address availability issues, take the following actions:

• Identify the subnets associated with the Amazon Redshift Serverless workgroup. You can find this information on the Amazon Redshift console or use the AWS CLI command get-workgroup.
• Check the available IP addresses in the associated subnets. You can view the available IP addresses in the Amazon VPC subnet details or use the AWS CLI command describe-subnets.
• Add additional subnets to the Amazon VPC. If the existing subnets don't have enough available IP addresses, then create new subnets in the same Amazon VPC and associate them with the Amazon Redshift Serverless workgroup. Verify that the new subnets are in different Availability Zones from the existing subnets.

Add a new subnet to the workgroup

To add a new subnet to your Amazon Redshift Serverless workgroup, complete the following steps:

1. Open the Amazon VPC console.
2. Create a new subnet in an Availability Zone within the same VPC as the existing subnets.
3. Open the Amazon Redshift console.
4. In the navigation pane, choose Serverless, and then choose Workgroups.
5. From the list of workgroups, select the name of the workgroup that you want to update.
6. In the Network and security settings section, choose Edit.
7. Select the Subnets tab.
8. Choose Add subnet, and then select the newly created subnet from the list.
9. Save the changes to the workgroup configuration.
10. Try to create the Amazon Redshift Serverless workgroup again.

If the error message persists, then contact AWS Support. You might have to provide details such as the VPC ID, subnet IDs, and the Amazon Redshift Serverless workgroup configuration.

Related information

Creating a Redshift provisioned cluster or Amazon Redshift Serverless workgroup in a VPC

Subnets for Redshift resources