AEM is often used in high impact deployments that might serve millions of users. In most cases, there are custom applications that are deployed on the instances, which add to the complexity. Any effort to upgrade such a deployment needs to be handled methodically.
This guide helps with establishing clear goals, phases and deliverables when planning your upgrade. It focuses on the overall project execution and guidelines. While it provides an overview of the actual upgrade steps, it refers to available technical resources where suitable. It should be used in conjunction with the available technical resources referred to in the document.
The AEM Upgrade process needs carefully handled planning, analysis and execution phases with key deliverables defined for each phase.
Note that it is possible to upgrade directly from AEM versions 6.0 and up to 6.5. Customers running 5.6.x and below need to upgrade first to version 6.0 or above, with 6.0(SP3) being recommended. Also, the new OAK Segment Tar format is used now for the Segment Node Store since 6.3, and repository migration to this new format is mandatory even for 6.0, 6.1 and 6.2.