Servers are high-powered computers built to store, process, and manage network data, devices, and systems. From a bird’s eye view, servers are the engines powering organizations by providing network devices and systems with adequate resources. For businesses, servers offer critical scalability, efficiency, and business continuity capabilities.
Whether it’s hosting a data-heavy website, setting up a shared drive for a department, or managing thousands of queries every minute, servers are the vehicles for hosting and processing-intensive workloads that go beyond the capabilities of a traditional computer.
This article looks at what servers do, types of servers, different server structures, and the operating systems (OS) servers use.
What Does a Server Do?
Servers can do everything a standard desktop computer can do and more. Vice-versa, computers can run server processes, but do so far less productively. Generally, servers offer the following features to the networks they serve:
- Scalability to serve a growing or fluctuating number of devices, users, and workloads
- High processing power with rising CPU and RAM specs to handle network workloads
- Reliability to ensure critical systems remain online and available
- Collaboration between personnel with access to shared network resources
- Cost savings over time because servers can reduce stress on network devices
The Client-Server Model
Servers that power other devices on the network are referred to as host servers. The in-network devices receiving resources from the host server are known as clients. The following graphic offers a quick look at how servers and clients work within a network.
Types of Servers
File Server
Used for storing files and folders, file servers save business data and make it accessible to networks. Examples include XMB, NFS, and NAS.
Domain Controller
Foundational to networks, domain controllers store the Active Directory and AD tools to manage users, permissions, devices, and group policies.
DNS Server
Adjacent to the domain controller, Domain Name Service (DNS) servers resolve the conversion of names into IP addresses for network systems.
Check out our Best Server Management Software & Tools for 2021.
DHCP Server
A Dynamic Host Configuration Protocol (DHCP) server automatically assigns network devices with the router, gateway address, DNS address, and IP address data.
Web Server
Imperative to web development, a web server hosts websites on the internet. It serves as an intermediary between users and the website’s backend database.
Application Server
Similar to a web server but designed to store application data, application servers host third-party apps and apps developed in-house for company use.
Read more: Web Servers vs. Application Servers.
Database Server
Serving as a repository of data, database servers host website and application information accessible via user queries on the frontend. (e.g., SQL, Oracle, MySQL)
Server Backup
Servers capable of receiving, holding, and restoring vast amounts of network storage are known as server backups. They help organizations prepare for the worst-case scenario.
Patch Server
The more extensive your network, the more likely you are to need an update server (or patch server) devoted to deploying updates. Patches resolve bugs and vulnerabilities and deliver new features for apps.
Proxy Server
Software or hardware-based proxy servers are responsible for filtering communications between web clients and service providers.
Virtual Server
Innovation in virtualization enables the creation of multiple virtual servers, also known as virtual machines (VM), on a single physical host machine through a hypervisor.
Phone Server
Connecting with a Private Branch Exchange (PDX), a phone server (or VoIP server) enables phone switching devices for managing internet-phone networks.
Print Server
For organizations with multiple locations or high printing needs, print servers manage the queue, resources, and logistics for network printers.
Email Server
Less common because of cloud solutions, email servers host email data. Examples of email servers would include SMTP relay or Microsoft Exchange Server.
FTP Server
A File Transfer Protocol (FTP) server — and its secure shell (SSH) encrypted brother, a Secure FTP (SFTP) server — is for storing files accessible to an external company.
Monitoring Server
A monitoring server handles the job of scanning the network and monitoring equipment health, as well as specs like CPU, RAM, and hardware space.
CCTV Server
Closed-circuit television (CCTV) servers or building security servers store audio, video, and sensor data related to the physical security of organization premises.
Terminal Server
A terminal server or remote desktop server enables remote users to access network resources for business continuity.
Load Balancing Server
For websites, applications, and software with varying and intensive workloads, load balancing servers can reallocate demands between other servers.
Check out our top picks for Best Load Balancers of 2021.
Types of Server Form Factors
Servers come in all shapes, sizes, and designs. However, the structure or form factor of servers typically falls into three types.
Rack Servers
A rack server is a general-purpose, mountable, and rectangular machine that stacks neatly into metal rack frames, thus optimizing space usage.
See the Top Rack Servers of 2021.
Blade Servers
A blade server houses multiple modular circuit boards called blades that don’t need CPUs, network controllers, and memory while also fitting in a rack frame.
See the Best Blade Servers for 2021.
Tower Servers
A tower server is a lightweight, stand-alone chassis most used by individuals and small businesses because of its strong configuration and customization features.
For a full breakdown of how servers differ by structure, read our Guide to Blade Servers vs Rack Servers vs Tower Servers.
Server Operating Systems
Server operating systems (OS) are the core programs that enable all server functionality. Operating systems for servers must be able to handle:
- Providing command-level interface (CLI) and/or a GUI display
- Comprehensive management of users, security, and processes
- Advanced hardware, software, and network configuration
- Managing and monitoring client computers, software, and activity
- Installing and deploying applications and patches to clients
Types of Server OS
- Linux OS
- Unix OS
- Windows OS
- Ubuntu OS
- Open Enterprise Server OS
- Red Hat Enterprise Linux OS
- Mac OS
Learn more about the most popular operating system for servers in our Best Linux Server Distros for 2021.
