Hi @manikanthar1295!
Please refer to my answer on this thread [1].
The recommendation is the same for most (if not all) versions of AEM.
[1] https://experienceleaguecommunities.adobe.com/t5/adobe-experience-manager/upgrade-6-2-to-6-5/qaq-p/4...
Citing my answer here for your ease:
There are different approaches to upgrade from older AEM versions to newer ones.
- In place upgrade - basically stopping your instance, replacing the quickstart.jar with the newer version and starting it again.
- Upgrade to a new environment - setting up a new environment with the target version and migrating your project (content, code, configurations, etc.) to that new environment.
From my experience the most reliable and clean way is a combination of these two approaches:
- Setup a new, clean environment with the target version.
- Perform an in-place upgrade on the old environment.
- Migrate everything from the old to the new instance (e.g. using the crx2oak tool).
The upgrade process includes rewriting/relocation/transformation of certain elements in the content. This step may get lost if you just migrate your content from an old 6.2 or 6.3 instance to a new 6.5 environment using a content migration tool, such as crx2oak.
Apart from the "pure" instance upgrade/migration, please also consider the following tasks that make sense and/or are necessary for an upgrade:
- Upgrade your JRE to the latest supported version. AEM 6.5 supports Java 8 and 11.
- Make sure to include the latest Service Pack on the target version (SP 8 for AEM 6.5).
- Perform some clean-ups and grooming on your repository before migration. Get rid of everything that is no longer needed, execute the common maintenance tasks (workflow and version purge) and run a repository compaction.
- Upgrade your projects dependencies (primarily the uber-jar).
- Refactor your code to ensure it's functioning as expected under the new version and with the new dependencies.
- Consider upgrading any 3rd party libraries, integrations and similar to their respective latest versions as well.
- Consider some code refactoring work to follow the latest recommendations and best practices, avoid usage of deprecated APIs/features/etc. and make your code base as modern, clean and up-to-date as possible.
- Consider automating the provisioning and configuration of your AEM environments.
Please also note: the bigger the upgrade version step, the more work it is. So plan to test the actual migration process, ideally on a production clone to ensure that you are comfortable with it and there are no surprises during the actual migration run.
Please also refer to these documentations:
Hope that helps!
