CentOS 8 Marketplace AMI sharing issue between accounts - 404 error when subscribing

The issue you're experiencing is related to the limitations of sharing AWS Marketplace AMIs between accounts. Unfortunately, it's not possible to directly subscribe to a CentOS 8 Marketplace AMI in the target account when it has been shared from another account. This is because Marketplace AMIs have specific licensing and subscription requirements that are tied to the original subscribing account.

To resolve this situation and migrate your data and workload to the target account, you have a few options:

1. Create a custom AMI: In the source account, create a new AMI from your running CentOS 8 instance that contains all the important data. This custom AMI can then be shared with and launched in the target account without Marketplace subscription issues.

2. Use AWS-native data transfer methods: Instead of sharing the entire AMI, you could use AWS services like AWS DataSync, AWS Transfer Family, or even simple methods like AWS CLI with S3 to move your important data from the source account to the target account. Then, in the target account, launch a fresh CentOS 8 Marketplace AMI and transfer your data onto it.

3. Utilize EC2 Image Builder: You could use EC2 Image Builder to create a custom image based on the CentOS 8 configuration, which can then be shared and used in the target account.

4. Consider using a non-Marketplace CentOS alternative: If possible, you might want to explore using a non-Marketplace CentOS alternative or another Linux distribution that doesn't have the same sharing restrictions.

Remember, when sharing AMIs between accounts, you're limited in terms of usage and modification. The receiving account can launch instances from the shared AMI but cannot delete, share, or modify it directly.

Whichever method you choose, ensure that you comply with the licensing terms of the original Marketplace AMI and any software installed on it. Also, be aware of any potential security implications when transferring data or creating custom AMIs.

Sources
Share an AMI with specific AWS accounts - Amazon Elastic Compute Cloud
AMI subscriptions in AWS Marketplace - AWS Marketplace