Server 2008
The core aim of Windows Server 2008 is to build in and deliver
security, reliability and performance. With these principles in
mind, Windows Server 2008 provides enhanced access controls,
flexibility of use for your IT infrastructure and the ability to
customize the computing experience based on the needs of your
users.
Many of the duties confronting IT professionals involve
controlling or managing the infrastructure of the organization
and maintaining and validating proper security of resources and
information. To maintain a highly efficient and secure
environment, IT professionals must find, obtain, learn and use a
wealth of tools and utilities. Because these tools usually come
from different sources, they're not integrated into the operating
environment, and therefore don't take full advantage of all the
power and flexibility available in an OS. Windows Server 2008
addresses these issues by integrating many required tools and
utilities into the OS, allowing for a more robust security model
and a lower cost of operations. This section covers changes made
to the core of the operating system.
Windows Server 2008 provides many more advances
than can be covered in this class. Therefore, this class provides
an overview of the features believed to be the most valuable to a
typical IT audience. You can go to the Microsoft website to learn about all the
features available in Windows Server 2008.
Understanding advancements in the Windows Server 2008
core
At the core of every OS is the kernel, which
manages all the resources available on a system: central
processing unit (CPU), memory and any input/output (I/O) devices
such as a printer, mouse and monitor. Sitting between
applications and the hardware, the kernel routes software calls
to specific devices and returns responses to the applications.
Because the kernel has full access to resources on the computer,
its security is paramount to overall system protection. The
kernel is also in a primary position for recognizing and
communicating any alerts that occur within the system.
Additionally, the kernel can route resource calls in a balanced
manner so that no resource is unduly overworked while others
remain idle.
Before the release of Windows Server 2008, many
of these tasks had to be performed by third-party software, which
can lead to system latency. With Windows Server 2008, several new
features are introduced that address these problems.
Hardened kernel architecture
A hardened kernel is one that's less
vulnerable to attack, smaller in size so that it requires fewer
resources to operate and contains the minimal code to provide all
the required functions. Windows Server 2008 has hardened its
kernel through several different methods:
- Selective installation: When installing
Windows Server 2008, you have the option of installing only the
features and services required for the server to perform the
functions you need. This means you can install a minimum of the
code for the kernel, plus any specific features you need to
customize your server.
To build a print server, for example, you install
the server core, which is the minimum code required for Windows
Server 2008, plus any services and drivers needed to communicate
with the printers on your network. You don't have to install any
other services, such as those that handle email or file
sharing.
- Flexible kernel services: You can move any
service that doesn't require highly secure access to resources
out of the kernel itself. These services are delivered in a layer
above the kernel layer. This is an additional level of protection
for the kernel in that it closes several potential security
gaps.
Services that need to communicate directly to the
CPU, memory or hard drive remain within the kernel.
- Kernel-level access and profile: You can
require every service running at the kernel level to be segmented
to a specific access level and to have a clearly defined profile.
This service profile states what and how services have access to
resources.
For example, if you have a service that requires
access to the CPU for a calculation and then must be able to
write a response to volatile memory, the service profile
specifies the type of access the service has to the CPU and the
type of write operation the service can perform. A service can't
perform any functions outside of its stated parameters in the
service profile. This closes potential attack vectors for
applications with malicious intent.
Standardized error-reporting capability
As hardware and software go about their regular functions,
they can sometimes run into an event, such as an error (minor,
major or catastrophic) or something of interest (such as a change
to a profile). These events are useful to programmers who are
developing and fine-tuning applications, quality assurance
personnel who need to determine what's happening behind the
scenes and operations personnel who monitor the health of systems
and applications and troubleshoot when errors are encountered. A
common challenge is how to identify, report and understand events
as they occur at the software and hardware level. Finding a
standard way of reporting and understanding events has required
third-party software and a great deal of recoding to make
applications perform to these standards.
Windows Server 2008 offers a solution to this problem by
building an event reporting mechanism into the kernel. The
Windows Hardware Error Architecture (WHEA) format provides
standards for hardware errors through plug-ins, a common format
for all error types and easier and uniform identification of
errors. This provides a simpler model for monitoring hardware.
The way this works is that software developers can build their
applications to conform to the WHEA standards. When an event
occurs in the application or the hardware, the kernel recognizes
the standard event output and sends it to a standard log format.
This simplifies the process of writing event code and
understanding event output.
Hot-swap and hot-replace advances
Chances are that you have become familiar with the concept of
hot swapping through the use of removable hardware, such as thumb
or flash drives. However, hot swapping essential system hardware
has traditionally been more challenging. Windows Server 2003
introduced the ability to add memory to a live system. In that
case, you could add memory to your system without turning the
system off, and the new memory would be almost instantly
available to running services.
In Windows 2008, this capability has been extended to allow
replacing the existing memory. If you have a faulty memory stick
in your server, for example, you can alert the OS that you want
to swap it out for another memory component. The kernel reroutes
live processes to other available memory and reroutes it to the
new memory once you complete your swapping tasks. Additionally,
you can hot-swap CPUs in Windows Server 2008 in much the same
way.