The 8 biggest mistakes in AEM cloud migration
...and how to avoid them
Typical errors occur again and again. Some companies only notice them when deployments fail, the new system runs more slowly or produces errors more frequently. The most unpleasant realization often comes too late, when the migration is not only more expensive than planned, but also unnecessarily painful. To prevent this from happening to you, I'll show you the 8 biggest mistakes in AEM cloud migration - and how to avoid them.
1. Ignore technical debt
Many AEM on-premise instances are lugging around a long list of technical legacy issues. Whether it's outdated Java versions, sling bundles that have been untouched for decades or outdated OSGi configurations - what used to "still work" quickly becomes a stumbling block in the cloud.
Older on-premise versions of Adobe Experience Manager, however, still run on Java 8, which requires a comprehensive code update. Third-party integrations such as direct database connections or SOAP interfaces are also possible in AEM Cloud. However, with restrictions. Every outgoing network connection can affect the request performance, as it runs in AEMaaCS via a managed network.
- Perform detailed code analysis to identify obsolete technologies.
- Update code and dependencies to Java 21 and the latest AEM SDKs.
- Connect external services asynchronously via Adobe I/O Runtime as microservices to keep the main application performant.
- Plan comprehensive tests in advance to identify problems at an early stage.
Unrecognized legacy issues increase technical debt exponentially. We recommend active prevention rather than fixing problems retrospectively.
2. Adopt old dispatcher and caching strategies
In the past, the dispatcher was the Swiss army knife for AEM. It filtered requests, handled URL rewrites, made pages faster and protected against overload. But in the cloud, other technologies take over these tasks. A global content delivery network (CDN) relieves the dispatcher considerably.
Cache invalidation replaces complete "clear cache" approaches. Instead of reloading everything, the cloud only updates modified content. If you stick with old purging rules, there is a risk of performance losses, inconsistent updates and high latency times.
- Radically streamline dispatcher rules.
- Understand CDN mechanisms and use them in a targeted manner.
- Set up cache invalidation properly instead of relying on complete purges.
The dispatcher as the go-to tool for everything? That is no longer the standard. Much is now controlled via the integrated CDN, optimized cache invalidation and the Cloud Manager - if you use these tools correctly, you save yourself unnecessary dispatcher workarounds.
3. Underestimate deployment and release process
Spontaneous deployments or quick editing on productive servers? That's no longer possible in the cloud. The Cloud Manager comes with rigid rules. Every change runs through pipelines that check for quality, security and performance.
The temptation to use workarounds does not pay off. Instead, deployment cycles are extended from hours to days or weeks in the event of errors.
- Adapt and optimize CI/CD pipelines.
- Integrate automated tests to minimize the need for manual intervention.
- Plan deployment and release properly instead of making ad-hoc adjustments.
The new paradigm of an end-to-end deployment and release strategy promotes long-term quality and stability.
4. Leave core components on old standards
AEMaaCS automatically updates Core Components to the latest versions. If you are still working with outdated or highly customized core components, this could result in display problems and faulty pages after an update.
In the past, core components were often overwritten unsuspectingly instead of extending them cleanly through derivation (inheritance) or delegation (delegation pattern). This is a fatal mistake, as even minor updates can cause massive disruptions.
- Update core components before a migration and adapt them to the cloud version.
- Implement adjustments through extensions instead of overwriting.
- Implement continuous integration tests and unit tests to ensure compatibility with future updates.
A reliable front end can only be realized with up-to-date, cleanly integrated core components.
5. Lack of access to operating system features
One of the biggest differences is the lack of direct access. No SSH, no manual access to production servers. Logs and configurations are provided via the Cloud Manager or managed in Git. Administrators need to get used to this considerably.
- Manage logs and dispatcher configurations exclusively via tools and repositories provided.
- Customize OSGi configurations exclusively via deployments.
- Monitor log files continuously via the Cloud Manager API. * Familiarize yourself with new processes and working methods.
- Accept that the cloud comes with its own access restrictions as a security feature.
This approach reduces risk and promotes efficient, standardized methods.
6. Migrate content fragments without tests
AEMaaCS comes with advanced tools such as a new Content Fragment Editor. However, APIs, queries and JSON structures can change in the process. If you adopt old structures without testing, you risk missing content or non-functioning queries.
- Check all content fragments for compatibility in advance.
- Continuously test your own customizations and GraphQL queries.
- Implement testing protocols and comparisons for all data used.
Without functioning content fragments, things quickly get lost in the cloud.
7. No collaboration between IT and the company
An AEM Cloud migration affects far more than the IT team. Marketing, editors and content teams use the platform on a daily basis. If they are not involved, chaos and misunderstandings often arise at the beginning.
Workflows change, authorizations shift - which significantly inhibits productivity without clear change management.
- Involve business teams in planning as early as possible.
- Prepare comprehensive training courses to prepare teams for change.
- Synchronize workflows and authorizations before going live.
Migration can only succeed if everyone involved works together.
8. Underestimated cost model
Cloud licenses follow a different pricing model than on-premise licenses. Instead of instances, content requests are the central license metric. Inefficient use of resources can result in unnecessary traffic costs.
Many companies justifiably expect lower total cost of ownership (TCO) as a result of cloud implementation. However, without sound planning, costs can also rise. This is because every request counts in the cloud - a poor cache configuration or oversized use of resources can drive up running costs unnecessarily.
- Ensure efficient caching and resource utilization.
- Clean-up of obsolete data and unused assets.
- Clarify pricing details with Adobe or your partner.
With the right measures, the cloud becomes a cost advantage instead of a cost driver.
Conclusion
The migration to AEMaaCS is not a simple hosting upgrade. I'm probably not telling you anything new. But if you simply move without considering the points mentioned above, you'll step into a cactus faster than you'd like. Adobe takes a lot of the hustle out of the equation with automatic updates, scalability and DevOps integration. But only if you question old habits, reduce technical debt and take your team with you. However, an AEM cloud migration has many more benefits than you might realize. Maybe it's even time to use Edge Delivery Services and make your architecture truly fit for the future - keyword Lighthouse Score 100. Anytime, anywhere.
Whether you are still in the planning phase or already in the middle of it: Let's talk!