/apps and /libs are immutable at runtime

Any content and subfolders in /apps and /libs is read-only. Any feature or custom code that expects to make changes there fails to do so. An error is returned that such content is read-only and the write operation was not able to complete. This has an impact in several areas of AEM:

  • No changes in /libs are allowed at all.

    • This is not a new rule, however this was not enforced in previous on-premise versions of AEM.
  • Overlays for areas in /libs that can be overlaid are still permitted within /apps.

    • Such overlays must come from Git by way of the CI/CD pipeline.
  • Static Template design information that is stored in /apps can’t be edited by way of the UI.

    • It is recommended that you use Editable Templates instead.
    • If Static Templates are still required, configuration information must come from Git by way of the CI/CD pipeline.
  • MSM Blueprint and custom MSM roll-out configurations must be installed from Git by way of the CI/CD pipeline.

  • I18n translation changes must come from Git by way of the CI/CD pipeline.

OSGi bundles and configurations must be treated as code

Changes to OSGi bundles and configurations must be introduced by way of the CI/CD pipeline.

  • New or updated OSGi bundles must be introduced through Git by way of the CI/CD pipeline.
  • Changes to OSGi configurations can only come from Git by way of the CI/CD pipeline.

The Web Console, used in previous versions of AEM to change OSGi bundles and configurations, is not available in AEM Cloud Service.

Changes to publish repository are not allowed

Aside from changes under the /home folder on the publish tier, direct changes to the publish repository are not allowed on AEM Cloud Service. In prior versions of on-premise AEM or AEM on AMS, code changes could be made directly to the publish repository. Some limitations can be mitigated in the following ways:

  • For content and content-based configuration: make your changes on the Author instance and publish them.
  • For code and configuration: make your changes in the GIT repository and run the CI/CD pipeline to roll them out.

Custom run modes are not allowed

Additional or custom run modes are not possible in AEM Cloud Service. For a list of run modes that are provided out-of-the-box for AEM Cloud Service, see Deploying to AEM as a Cloud Service.

Removal of Replication Agents and related changes

In AEM Cloud Service, content is published using Sling Content Distribution. The replication agents used in previous versions of AEM are no longer used or provided, which might impact the following areas of existing AEM Projects:

  • Custom workflows that push content to replication agents of preview servers for example.
  • Customization to replication agents to transform content.
  • Using Reverse Replication to bring content from Publish back to Author.

In addition, the pause and disable buttons are removed from the replication agent administration console.