NetWare Cluster Services assumes that NetWare 5 or NetWare 5.1 has already been installed. The following concepts and terms help you understand how NLS supports the UAL model and NetWare Cluster Services
Server base license upgrade certificate---A license certificate that replaces a NetWare 5 or NetWare 5.1 server base license. See NetWare Cluster Services Licensing.
Typically, a server base license certificate is installed during a NetWare 5 or NetWare 5.1 installation. The license certificate is for the Server Connection License (SCL) model and allows the NetWare 5 operating system to provide authenticated connections for clients.
A License Container object for a server base license displays as follows:

When you install NetWare Cluster Services, a server base license upgrade (SBLU) certificate replaces the server base license certificate. This SBLU certificate is installed into the existing License Container object and (in NetWare Administrator) displays the same as the server base license certificate.
NOTE: MLA sites that use "unlimited" certificates don't need to delete server base license certificates and install SBLU certificates.
Cluster user access license certificate---A license certificate that enables users to connect to any server in a NetWare Cluster. See NetWare Cluster Services Licensing. Typically, a connection license certificate is installed during a NetWare 5 or NetWare 5.1 installation. This license certificate is for the SCL model and enables users to connect to NetWare servers and use network services. NLS creates a License Container object for a server connection license certificate and stores the certificate there. A License Container object displays as follows:
When you install NetWare Cluster Services, a cluster user access license certificate replaces the connection license certificate. During this task, NLS creates a License Container object for the CUAL certificate and stores the certificate there. A CUAL License Container object and license certificate display as follows:
NOTE: MLA sites that use "unlimited" certificates don't need to delete connection license certificates and install CUAL certificates.

Cluster Server License (CSL)---A license certificate that enables a server to function in a cluster and provide failover functionality. See NetWare Cluster Services Licensing. When you install NetWare Cluster Services, you install a cluster server license (CSL) certificate, which displays as follows: