The Basics of How a Server Works and How Virtualization Lets it Work Better
AbleIT likes to make work easy. Part of making work easy is demystifying how IT works. Servers are one of the most known pieces of hardware of a network. But what do they do? Also, what is virtualization and why is it useful? These are questions we hope to answer in this article.
A server is what holds the systems, programs and databases that allow your network, programs and technology to function. The server also provides the power to make these systems work. The core components of a server are CPU, memory and hard drive. These components work together to give you access and function.
Here’s a brief breakdown of the services that a server holds:
a. Domain Controller: This is what keeps usernames, passwords and applies rights or access to the network and programs.
b. Active Directory (AD) and Domain Name System (DNS): Active Directory provides the authorization for the usernames and passwords in the Domain Controller. The DNS turns user names into IP address to be used in the network as that is how devices are identified through the internet.
c. DHCP: This is what hands out IP addresses.
d. Print Server: This is where access to your printer is held. This allows printers to be shared. Otherwise only one person could use a printer.
e. Anti Virus Console, Spam, Back up: These are referred to as utilities, hosting them on the server allows administration and monitoring to be done centrally instead of individually on each workstation.
f. File Server: This gives the ability to have shared files and is managed by the AD.
g. SQL Server: This is a database engine. It holds and provides access to the data of specific software like sage, office tools, quick books etc. It allows data to be managed centrally vs on individual machines.
h. Exchange Server: This, simply put, gives you access to your email. It holds and deals out the email to individual accounts.
i. Terminal Server: Instead of having individual workstations have their own applications like office, adobe etc this system will hold them all and provide access individually. It works by you logging in to your workstation and then logging in to the terminal server giving you access to all your programs like word, excel, sage, adobe etc.
j. Back up and Disaster Recovery Console: similar to other consoles having the service located on the server allows management and back up to be done centrally instead of done individually on each machine.
What virtualization works is it groups and separates these services so that they act individually instead of all at once.
The groupings act like individual servers. The way that we typically group is:
a. DC Group: This holds the domain controller, AD, DNS, DHCP and print server.
b. File Utility Group: This will contain the file server and all the utilities.
c. SQL Group: This will hold the SQL server, the database. It is large enough that it needs its own grouping.
d. Exchange Group: like the SQL we find Exchange works best on its own.
e. Back up & Disaster Recovery Group: This will hold back up and disaster recovery systems.
f. RDS Group: This will hold the terminal server.
Back in the day there would be no virtualization and each of these groupings would be on there own physical server. Advancements have been made that increase the power of servers and allows everything to be on one.
Virtualization is needed because without the layers separating these groups and services everything is competing for the same resources at once. When virtualizing you can dedicate specific amounts of computing power, ram and hard drive space to specific groups. Virtualizing is like budgeting vs dumping a bag of cash on the table. Budgeting allows you to give money to different departments as you need them vs a free for all until it’s gone.