Atlassian Crowd support is preinstalled and ready to configure in Nexus Professional 2.7+.
In older Nexus versions, Nexus Crowd support is implemented as an optional plugin that comes as part of any Nexus Professional download. The directory containing the plugin code is called either enterprise-crowd-plugin-X.Y.Z or nexus-crowd-plugin-X.Y.Z. Install the plugin following the instructions in Section 22.1, “Managing Nexus Plugins”.
Using LDAP and Crowd Realms together in Nexus may work, but this is not supported. If you already use Nexus LDAP support, we recommend adding your LDAP server as a Crowd directory accessible to the Crowd nexus application instead of using both LDAP and Crowd realms in Nexus.