AWS Marketplace AMI Licensing Issues in Cross Account Amazon EC2 Migration

Introduction

Cloud migration projects often seem straightforward until hidden dependencies such as licensing, encryption, and unsupported operating systems create unexpected challenges. During a recent AWS account-to-account migration, a routine Amazon EC2 workload migration exposed issues with AWS Marketplace licensing and the end-of-life CentOS 7 operating system. This blog covers the root cause, remediation approach, and key lessons learned from migrating a Marketplace-based Amazon EC2 workload across AWS accounts.

Background and Migration Scenario

The customer was undergoing a multi-account AWS transformation to improve governance, security, and operational management. As part of this initiative, multiple Amazon EC2 workloads, AMIs, EBS snapshots, and cross-account AWS IAM and AWS KMS configurations were migrated to a new AWS account. The migration used an AMI-based approach to minimize downtime and simplify workload portability by:

1. Creating AMIs from source Amazon EC2 instances
2. Sharing them with the target account
3. Launching workloads in the destination environment

While most workloads migrated successfully, a legacy CentOS 7 application server proved a major challenge during the migration.

The Amazon EC2 Launch Failure

The migration process initially appeared successful. The Amazon EC2 instance was converted into an AMI, the AMI was shared with the destination account, and all required snapshots were accessible. The AMI was also visible in the target account console, which usually confirms that sharing permissions are correctly configured.

However, the problem surfaced when attempting to launch a new Amazon EC2 instance from the shared AMI. The launch operation repeatedly failed.

The initial troubleshooting focused on common cross-account migration issues, such as:

• Incorrect AMI permissions
• Snapshot access problems
• KMS encryption restrictions
• IAM trust policy errors

After validating all configurations, no infrastructure or permission-related issues were identified. This indicated that the root cause extended beyond traditional migration dependencies.

Root Cause Analysis

The breakthrough came after analyzing the AMI origin more closely. The CentOS 7 workload was built using an AWS Marketplace image, which introduced an account-level licensing dependency. Although AMIs can be shared across AWS accounts, the target account must also have an active subscription to the Marketplace product to launch instances successfully.

In this case:

• The source account already had entitlement to the CentOS 7 Marketplace image
• The target account had no Marketplace subscription
• Amazon EC2 launch operations were therefore blocked

The issue was not related to AWS IAM, networking, or storage configurations, but entirely due to AWS Marketplace licensing. This highlighted an important migration lesson: readiness assessments must include Marketplace and licensing validation in addition to standard infrastructure checks.

The Bigger Risk: CentOS 7 End-of-Life

After identifying the AWS Marketplace dependency, another major concern emerged: the application was running on CentOS 7, which had already reached end-of-life. This introduced risks, including a lack of vendor support, missed security updates, compliance concerns, and long-term operational instability. Although the licensing issue could be resolved temporarily, migrating the workload “as-is” would only carry forward unsupported infrastructure into the new environment. As a result, the migration evolved into a broader modernization initiative focused on long-term security, sustainability, and governance.

Two-Phase Migration Strategy

To balance immediate migration requirements with long-term modernization goals, a two-phase strategy was implemented.

Phase 1: Migration Continuity

The primary objective was to complete the migration within the planned maintenance window while minimizing downtime.

The remediation steps included:

• Subscribing to the CentOS 7 Marketplace product in the target account
• Accepting Marketplace licensing terms
• Validating account entitlement
• Relaunching the shared AMI

Once the AWS Marketplace subscription was activated, the Amazon EC2 instance launched successfully in the destination account. Application validation checks passed, and the migration wave was completed within the approved timeline.

This ensured immediate business continuity without delaying the broader migration program.

Phase 2: Operating System Modernization

With the workload stabilized in the target environment, the focus shifted toward modernization.

The long-term remediation plan involved:

• Migrating the workload to Amazon Linux or Red Hat Enterprise Linux (RHEL)
• Rebuilding the application stack on a supported platform
• Revalidating integrations and dependencies
• Updating security, patching, and monitoring baselines

By separating “migration continuity” from “modernization,” the customer avoided unnecessary downtime while still addressing technical debt and security concerns.

AWS Services Used

• Amazon EC2
• AMIs and EBS Snapshots
• AWS IAM
• AWS Marketplace
• AWS KMS
• Amazon CloudWatch

Lessons Learned and Best Practices

1. Validate AMI Origins

Always identify whether workloads rely on:

• Marketplace AMIs
• Community images
• Custom enterprise images

Licensing dependencies should be documented during the migration discovery phase.

2. Include Licensing in Migration Readiness

Marketplace subscriptions should be treated as mandatory prerequisites for migration rather than optional validations.

3. Verify Operating System Lifecycle Status

Migration projects are excellent opportunities to modernize unsupported or deprecated operating systems.

4. Separate Migration from Modernization

When migration timelines are tight:

• Prioritize continuity first
• Execute modernization in a planned secondary phase

5. Align Migration with Governance Goals

Cloud migrations should improve:

• Security baselines
• Governance standards
• Patch management
• Platform sustainability

Organizations should avoid replicating legacy technical debt in new cloud environments.

Conclusion

This migration engagement demonstrated that successful cloud migration extends far beyond simply moving infrastructure between AWS accounts. Hidden AWS Marketplace dependencies, unsupported operating systems, and licensing constraints can significantly impact migration success if not identified early in the planning phase.

Drop a query if you have any questions regarding AWS Marketplace, and we will get back to you quickly.