Licensing Requirements

Licensing Requirements

Licensing is easily the most complex subject in a server-based computing environment. The reason is not that the topic is hard to understand but that the vendors are constantly changing the requirements, and with frequent operating system upgrades and application upgrades, figuring out how to stay compliant is always a challenge. In this chapter, we briefly touch on the requirements because going into detail is beyond the scope of this book, which concentrates on the Citrix Certified Administrator exam.

You need to familiarize yourself with two major components : server licenses and client licenses. Let's tackle the server licenses first.

Server Licenses

The first component to license should be the server operating system that will host all the other applications installed on it. It is important to understand what needs to be licensed on a Windows 2000 Server and Windows Server 2003 OS to avoid connection issues later.

Both Windows 2000 Server and Windows Server 2003 have the same licensing requirements with different upgrade paths. It is best to consult your Microsoft representative to ensure you are abiding by the Microsoft guidelines for Terminal Server (TS).

Two types of licenses are required when you are running Terminal Services with Citrix MetaFrame Presentation Server 3.0:

• Windows 2000/2003 Server License This is the core product license, the base Windows server operating system. You need a license to install the operating system.

• Citrix MetaFrame Presentation Server 3.0 Server license A license is required to install the MetaFrame server software. The nice thing about Citrix MetaFrame is you have to buy only one copy of the MetaFrame Presentation Server product. After you own a license, you can install it as many times as you want on as many servers as you like. The catch is that Citrix wants to charge on the connection licenses, which we discuss in the next section, instead of charging every time you install the server product.

Client Licenses

After tackling the server licensing requirements, we arrive at the client licensing requirements. Every client that accesses a Microsoft Terminal Server or a Citrix MetaFrame Presentation Server needs a client license to be able to access the resources on the server. You also need a client license to be able to log in and use the functionality of the MPS server.

The following license requirements should be addressed in any Terminal Server or Citrix MPS environment:

• Windows 2000/2003 Server Client Access Licenses (CALs) You need a CAL to authenticate and use other server resources such as printing or file sharing.

• Windows 2000/2003 Terminal Server Client Access Licenses (TSCALs) In addition to the CALs that are required, a TSCAL is also required. For a user to log in and use the Terminal Services functionality of the server, a TSCAL is necessary. It simply licenses the TS portion of the operating system.

• Citrix MetaFrame Presentation Server 3.0 Connection Licenses These licenses are needed to allow users to log in to the MetaFrame Presentation Server and take advantage of its services.

• Citrix Migration Licenses These licenses are used to migrate to a newer version of MetaFrame. For example, if you are upgrading to MPS 3.0 from MF 1.8 or MetaFrame XP, you can use your existing licenses and migrate them. Consult with your Citrix representative to see whether you qualify for these licenses.

• Citrix Upgrade Licenses These licenses are used to upgrade the version of MetaFrame within the same family. For example, if you have deployed MPS 3.0 Advanced Edition and you decide you need the features of the Enterprise Edition, you would purchase upgrade licenses from Advanced Edition to Enterprise Edition.

• Application Licenses These licenses are required for any applications that you install on the MPS server. You should consult with each application's vendor as to how licensing is treated on a Terminal Server.

Citrix Connection Licenses

Citrix Connection Licenses allow users to connect to any resource in the farm and launch as many applications as they want and yet consume just one license. These licenses are the equivalent of Per Seat licensing in Windows 2000 Server or Windows Server 2003. The difference is that this type of license is not permanently attached to the user using it. Licenses are assigned from a pool for a user to use during his or her sessions; after the user logs off, all session connectivity to the farm for the license is released and made available for other users to use.

In other words, if Didi logs on to the server farm and launches Microsoft Word on Server A, then launches JDEdwards One World (a financial software package) on server B, and then launches Report Writer on Server C, she is still consuming just one license yet running three sessions to three different servers in the server farm. After Didi logs out of all three applications, the license assigned to her is put back into the pool.

Alert

Given a license scenario, make certain you can identify any missing licenses and provide the proper recommendations to ensure license compliance and avoid outages due to a shortage of available licenses.