One of the most important steps in a Microsoft Dynamics NAV implementation
is the selection of the hardware and software platform.
When planning a Microsoft Dynamics NAV 2009 installation, you must make
sure that the computers that will be used meet the minimum requirements and are
sufficient for your current and future needs. Failure to meet these specifications
can cause the installation of some or all of the components to fail.

Hardware Requirements

Microsoft Dynamics NAV does not require particularly sophisticated equipment,
but as with all programs, the better your equipment, the better the results. You
get the best solution with the optimal equipment and with the program settings
optimized for that equipment.
In a multi-user installation, you can, in principle, use the same type of computer
for both the clients and the server. However, there is a difference in how much
CPU power, memory, and disk space the client and server will need.
Computers for servers that run Windows Server 2003 or Windows Server 2008
must comply with the requirements specified by Microsoft. If you use the
Microsoft Dynamics NAV SQL Server option, the hardware must meet the
specifications of both the operating system and the Microsoft SQL Server
edition.

The database is stored on the server, making it a critical area of the application
because several users can access it at the same time. Therefore, it is important to
select a powerful computer for the server. In addition, the following are aspects
of the server that require additional consideration:
• The hard disk and controller
• The RAID system
• The memory
• The network adapter
• The CPU

RAID (Redundant Array of Independent Disks)

RAID systems provide two main advantages: reliability (RAID 1 or mirrorin
and performance (RAID 0 or striping). Given the low cost of hard drives, any
company should at least implement RAID 1 to be more secure from data-loss
Whether you use RAID 0 depends on the number of transactions the system
required to handle. The advantage of RAID systems is that you can add disks
over time and improve performance or increase capacity.
A RAID system consists of several disks. The key feature of a RAID system
that the failure of one disk does not bring the entire system down.
Several RAID configurations exist. The most important configurations are
described below.

RAID Level Description

RAID 0 This level is also known as disk striping because it uses a disk
file system called a stripe set. Data is divided into blocks and
spread in a fixed order among all disks in an array. RAID 0
improves read and write performance by spreading operations
across multiple disks.
RAID 0 is similar to RAID 5, but RAID 0 does not provide
redundancy (fault tolerance).

RAID 1 Called mirroring. The data is written redundantly to pairs of
drives and can be read independently from each drive. This is
fast and provides full redundancy, but the disk capacity
required is doubled. The read performance can be up to twice as
fast as a single drive because both drives can process the read
request simultaneously. Write performance is almost
unchanged. RAID 1 is best for transaction processing, where
many small I/Os are required. RAID 1 is also the most
expensive RAID configuration because of the disk overhead.
In theory, RAID 1 has twice the read transaction rate of single
disks and the same write transaction rate as single disks.

RAID 5 Also known as striping with parity, this level is the most
popular strategy for new designs. RAID 5 stripes the data in
large blocks across the disks in an array. The parity for the
stripes of data is also spread across all of the drives, so no one
drive is dedicated to parity. Data redundancy is provided by the
parity information. The data and parity information are
arranged on the disk array so that the two types of information
are always on different disks. In general, striping with parity
offers better performance than disk mirroring (RAID 1).
RAID 5 requires a minimum of three drives to implement. It
has the highest read transaction rate, but a medium write
transaction rate.

RAID 10 RAID 10 uses a mirrored array of disks (RAID 1 array) that are
(1+0) striped to another set of disks. RAID 10 is not to be confused
with RAID 0+1.

RAID 0+1 This level is also known as mirroring with striping. RAID 0+1
uses a striped array of disks that are then mirrored to another
identical set of striped disks. For example, a striped array can
be created by using five disks. The striped array of disks is then
mirrored using another set of five striped disks. RAID 0+1
provides the performance benefits of disk striping with the disk
redundancy of mirroring.

RAID Levels and SQL Server

RAID is a disk system that contains multiple disk drives, called an array, to
provide better performance, reliability, storage capacity, and reduced cost. Fault-
tolerant arrays are categorized in six RAID levels: 0 through 5. Each level uses a
different algorithm to implement fault tolerance.

Although RAID is not a part of SQL Server, implementing RAID can directly
affect the way SQL Server performs. RAID levels 0, 1, and 5 are typically used
with SQL Server.

A hardware disk array improves I/O performance because I/O functions, such as
striping and mirroring, are handled efficiently in firmware. Conversely, an
operating system-based RAID offers reduced cost, but consumes processor
cycles. When cost is an issue and redundancy and high performance are required,
RAID 5 volumes are a good solution.

Data striping (RAID 0) is the RAID configuration with the best performance, but
if one disk fails, all the data on the stripe set becomes inaccessible. A common
installation technique for relational database management systems is to configure
the database on a RAID 0 drive and then put the transaction log on a mirrored
drive (RAID 1). You can obtain the best disk I/O performance for the database
and maintain data recoverability through a mirrored transaction log, assuming
you perform regular database backups.

RAID 5 provides redundancy of all data on the array. This allows for a single
disk to fail and be replaced most of the time without system downtime. Be aware
that RAID 5 offers reduced performance compared to RAID 0 or RAID 1
(because of the parity overhead), but better reliability and faster recovery. Write
performance on RAID 5 increases when more disks are added to the RAID 5
array. In general, read performance is better in RAID 5 than in RAID 1 (as RAID
5 has at least three disks, whereas RAID 1 has only two). For ERP systems, with
many write transactions, RAID 5 is not always the best solution.