In Server Manager, all sites are preserved even when the software has been uninstalled.
If you are transferring your sites from one server to another, or if you need to
rebuild the underlying server operating system and cannot keep the local file structure
during the upgrade, you must first export your site configurations before upgrade.
After upgrade, you must then import your exported sites and update them. For more
information on exporting site configurations, see Export a configuration. For information on importing site configurations, see Import a previously saved configuration.