Microsoft has greatly simplified the
licensing and version options for Windows Server 2012. There are
effectively only two versions of Windows Server 2012 now: the Standard
edition and the Datacenter edition. Microsoft eliminated the Enterprise
edition and the Web edition of the software, which effectively just
enabled or disabled feature sets. In a virtualized world such as we’re
in, organizations really only choose the density of their
virtualization, whether they are running physical (or lightly
virtualized systems) or that they are heavily virtualizing their server
environment. So, the two versions fulfill those requirements.
When installing Windows Server 2012,
beside choosing Standard or Datacenter editions, the installer of
Windows will choose either the full graphical user interface (GUI)
version of Windows Server or a the non-GUI version called Server Core.
Windows Server 2012 Standard Edition
The Windows Server 2012 Standard Edition is
the recommended version of Windows Server for a physical server that
won’t usually be virtualizing guest sessions. The Standard edition
provides a license for the physical system, and includes all the features and functions built in to Windows Server 2012.
Unlike in the past, where the Standard
edition did not do clustering or had caps on the amount of memory
supported by the system and the like, with Windows Server 2012, the
Standard edition has all the same features/functions as the Datacenter
edition, just supports fewer simultaneous virtualized guest sessions.
A basic Windows Server 2012 x64-bit Standard
edition system supports all the server roles available in Windows
Server 2012. It is a good version of the operating system for physical
servers (high-performance database servers, standalone web servers, and
the like).
It used to be you put utility servers (such
as DNS or DHCP), file servers, print servers, media servers, and domain
controllers on the Standard edition of Windows. In a highly virtualized
environment, however, these servers are simply guest sessions of a
larger Windows Datacenter edition host system. The good thing with the
new licensing model for Windows is that you don’t have to worry about
capacity planning and starting off “small” with Standard edition and
then having to completely rebuild the Standard edition servers with an
Enterprise or Datacenter edition as your needs grow. The new licensing
model simplifies implementation solely on the density of servers
that’ll be virtualized on a system.
Note
One of the first things an organization becomes aware of is that Windows Server 2012 comes in 64-bit (x64) versions only.
32-bit hardware and a 32-bit installation is not supported. The most
recent version of the Windows Server operating system that supports
32-bit is Windows Server 2008.
Windows Server 2012 Datacenter Edition
Windows Server 2012 Datacenter edition is the
most common license organizations buy these days because the Datacenter
edition provides support for an unlimited number of virtual guest
sessions on the server. So, in a highly virtualized environment where a
server might be running 5, 6, 8, 10 guest
sessions, the Datacenter license is a flat cost, and therefore it gets
cheaper per guest session every time additional sessions are added to a
server.
Unlike early editions of Windows Datacenter
edition that only worked on proprietary hardware, the Datacenter
edition of Windows Server 2012 is nothing more than a different way of
licensing the software. The code is basically the same across the
Standard edition and Datacenter editions. As noted about the Standard
edition, there are no limitations in features in the Standard edition.
All features and functions, including clustering, load balancing,
certificate services, and so on, are included in the Standard edition
and the Datacenter edition. So, only from a licensing standpoint does
an organization end up being able to support more guest sessions with
Datacenter than with Standard edition.
An organization can scale out or scale up its server applications. Scale out refers to an application that performs better when it is distributed across multiple servers, whereas scale up
refers to an application that performs better when more processors are
added to a single system. Typical scale-out applications include web
server services, electronic messaging systems, and file and print
servers. In those cases, organizations are better off distributing the
application server functions to multiple Windows Server 2012 systems.
However, applications that scale up, such as e-commerce or data
warehousing applications, benefit from having all the data and
processing on a single server cluster. For these applications,
centralization for scalability purposes provides the added benefit to
the organization. In either case, though, with Windows Server 2012, the
version of the license (Standard or Datacenter) has no impact on how
the organization is forced to deploy the application; it is now up to
the organization to decide the best application architecture fit.
Windows Server 2012 Server Core
Initially introduced in Windows Server 2008
and now supported also with Windows Server 2012 is a Server Core
version of the operating system. Windows Server 2012 Server Core, shown
in Figure 1,
is a GUI-less version of the Windows Server 2012 operating system. When
a system boots with Server Core installed on it, the system does not
load up the normal Windows GUI. Instead, the Server Core system boots
to a logon prompt, and from the logon prompt the system drops to a DOS
command prompt. There is no Start button, no menu—no GUI at all.
Figure 1. Windows Server 2012 Server Core.
Server Core is not sold as a separate
edition, but rather as an install option that comes with the Standard
and Datacenter editions of the operating system. So, when you purchase
a license of Windows Server 2012, the DVD has both the normal GUI
edition code plus a Windows Server 2012 Server Core version.
The operating system capabilities are limited
to the edition of Server Core being installed, so a Windows Server
2012, Standard edition Server Core server has the same functionality as
the GUI version of Windows Server 2012 Standard edition.
Server Core has been a great version of
Windows for utility servers such as domain controllers, DHCP servers,
DNS servers, IIS web servers, and Windows virtualization servers
because the limited overhead provides more resources to the
applications running on the server, and by
removing the GUI and associated applications there is less of a
security attack footprint on the Server Core system. Because most
administrators don’t play Solitaire or use Media Player on a domain
controller, those are applications that don’t need to be patched,
updated, or maintained on the GUI-less version of Windows. With fewer
applications to be patched, the system requires less maintenance and
management to keep operational.
Note
With the Server Manager remote administration capabilities of Windows Server 2012, administrators can now remotely manage a Server Core system from the
Server Manager GUI interface on another server. This greatly enhances
the management of Server Core hosts so that administrators can use a
GUI console to manage the otherwise GUI-less version of Windows Server.
Those who have tried Server Core in early
editions of Windows (2008 or 2008 R2) may have found the nongraphical
experience with Server Core to not be pleasant or event usable. With
SConfig on the Server Core system, server administrators can now have a
graphical-like experience for configuring server name, IP address,
joining the domain, and the like and do not have to remember long text
strings for configurations. Additionally, the new Windows 2012 Server
Manager console allows remote installation of server roles, features,
and the like that greatly improves the experience of setting up Server
Core.
In addition, Microsoft provides the
ability for an organization to take a Server Core system, temporarily
make the Server Core system into a GUI-version of Windows (to
potentially install an application, drivers, and so on) and then drop
the configuration back down to Server Core once installed. This
provides the best solution for applications that may have previously
not been supported in installing on Server Core to be installed in a
GUI console, and then remove the GUI back down to a base Server Core
system.
