Overview of Active Directory Authentication with XenServer

AD authentication in a XenServer environment

Even though XenServers are Linux-based, XenServer lets you use Active Directory accounts for XenServer user accounts. To do so, it passes Active Directory credentials to the Active Directory domain controller.

When added to XenServer, Active Directory users and groups become XenServer subjects, generally referred to as simply users in XenCenter. When a subject is registered with XenServer, users/groups are authenticated with Active Directory on login and do not need to qualify their user name with a domain name.

Note: By default, if you did not qualify the user name (for example, enter either mydomainmyuser or myuser@mydomain.com), XenCenter always attempts to log users in to Active Directory authentication servers using the domain to which it is currently joined. The exception to this is the LSU account, which XenCenter always authenticates locally (that is, on the XenServer) first.

The external authentication process works as follows:

  1. The credentials supplied when connecting to a server are passed to the Active Directory domain controller for authentication.
  2. The domain controller checks the credentials. If they are invalid, the authentication fails immediately.
  3. If the credentials are valid, the Active Directory controller is queried to get the subject identifier and group membership associated with the credentials.
  4. If the subject identifier matches the one stored in the XenServer, the authentication is completed successfully.

When you join a domain, you enable Active Directory authentication for the pool. However, when a pool is joined to a domain, only users in that domain (or a domain with which it has trust relationships) can connect to the pool.


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