Confluence: How do I upgrade Confluence single server installation to Data Center?
How do I upgrade a Confluence Server installation to Confluence Data Center?
To use Confluence Data Center you must:
If you plan to run Confluence Data Center in a cluster there are some additional infrastructure requirements. See Clustering with Confluence Data Center for more information.
To get started
Moving from a standalone to a clustered setup
From Confluence 7.2 onwards, you can upgrade from Server to a standalone Data Center installation, then enable and configure your Confluence cluster.
For step-by-step instructions, see Migrate from Server to Data Center.