What’s the Importance of Linux Server Roles?
If you're new to the world of Linux, you may have found yourself in the middle of a hotly debated topic, one that has seemingly lasted since the inception of the modern operating system. What is that topic, you might ask? Well, Linux versus Windows, of course.
In this post, we aren't going to pretend to address that question, because, in reality, both Linux and Windows offer different layers of value to both the organization and the admin running that environment; however, we are going to discuss some aspects of Linux that has won over the hearts of many admins and fueled this debate — more specifically, server roles.
What Exactly are Linux Server Roles?
Linux servers can be configured in a variety of ways to accomplish different tasks. From file servers, email servers to desktops, Linux can be configured in many different ways to meet the demands of today's modern business.
Depending on the specific services that are installed and enabled on that server, the Linux server will have the functionality to perform specific tasks. This, in a nutshell, is the concept of Linux server roles. Server roles define the use and responsibility of a given server based on the services installed on the server.
Overview of Common Linux Services
As mentioned, Linux roles are defined by the services installed on the Linux server to enable specific server responsibilities. So, before we dig into server roles in any more detail, let’s take a look at a brief overview of common Linux services.
Authentication Services. One of the most critical aspects of any dynamic IT infrastructure supporting the needs of a given business is authentication services. Authentication services build and maintain username and password credentials for users within the organization.
Certification of Authority. A certification of authority or CA is a service responsible for generating digital certificates to verify identity within an organization. Oftentimes, organizations will build private certification authority such that only authorized users within the domain can be validated via CA to perform certain tasks or access certain services.
Clustering. Clustering is another service that provides a tremendous amount of value to organizations in how computing resources and computing availability is managed. Clustering is the concept of multiple servers sharing production resources such that, if one server were to suffer an outage redundancy, the high availability of the other clusters in the node will ensure that the organization does not suffer any downtime or loss of business continuity.
A common implementation of clustering can be found in the process of designing a MySQL cluster. MySQL is a Linux-based relational database used for storing critical table-based information. Often, organizations will build MySQL clusters to minimize the likelihood that a company will suffer any loss of data should one of the nodes in a MySQL cluster go down.
Database. Database services are critically important for the day-to-day processing of an organization. As mentioned above, in the world of Linux, organizations often run MySQL relational databases to store important table-based information. Often these databases are used for data warehousing, customer information management, and web databases.
DHCP Services. DHCP Services, or Dynamic Host Configuration Protocol Services, is a service used to dynamically assign IP addresses to network-attached devices within the network. This dynamic IP assigning is critically important in the sense that it allows devices within the network to communicate with other devices, and it helps route traffic from the outside world (the internet) to these network-connected devices. Without DHCP services, internal users would not be able to easily communicate with other devices on the network, and the outside world would not be able to communicate with devices inside the network.
DNS Services. A DNS service can be thought of as the phonebook of the internet. When you or I want to access a website, we typically think of the website URL associated with the name of the company. For example, if we are looking to visit Google, we'll direct our web browser to take us to Google by typing in www.google.com, right? Well, behind the scenes, it's the DNS service that is dynamically mapping domain names to IP addresses to facilitate this process. The reason for this is because internet routing architecture and the computing architecture behind it don't understand the names of organizations in the same way it understands IP addresses, just how you most likely don't remember the IP address of Google.com off the top of your head.
Overview of Common Linux Server Roles
Now that we've discussed the importance of some common Linux services and how these services enable Linux server roles, let’s look at some of the common Linux server roles you may come across as a Linux admin.
Distributed File System. A distributed file system or DFS is a file system that is distributed among many file servers that can span multiple locations with the intention to create network-based shared access to files. The concept of a distributed file system is designed to present a network-accessed file storage such that all users within a network with proper permissions have access to add, delete or collaborate on files presented in the shared file system.
Domain Controller. A domain controller manages all of the authentication requests dependent on predetermined user permissions, user roles, and role-based access architected within an environment. Often, this user role ecosystem is defined through services such as Active Directory or Linux-centric services like OpenLDAP.
Print Server. A print server is a dedicated server to support in-network printing requests. Often this server will run pre-installed and configured print services and run dedicated printer drivers to support the unique printer appliance that you've selected to manage the print requests.
Web Server. A web server is designed to store and present website assets and content for a website. Typically web servers are designed to run on a relational database backend such as MySQL or PostgresSQL that house and maintain all of the specific websites attributes that are needed to run a dynamic website. This web server communicates with a web browser using HTTP and styles the webpage using HTML and CSS to present the dynamic and interactive websites that we know and use today.
Email Server. An email server is a server dedicated to sending and receiving email. To effectively facilitate the email process, email servers must have predefined email software and services on the physical or virtual server. These services allow Linux administrators to design and manage email accounts for hosted domains on the server. Further, Linux admins will be tasked with further configuring the mail server using certain mail protocols such as SMTP, IMAP, or POP3. Without going into too much technical detail, SMTP mail servers support outgoing mail, whereas IMAP and
POP3 servers handle receiving mail messages.
How Does Linux Stand Up to Other Architectures?
Now that we've uncovered the importance of Linux services and Linux server roles, you may be wondering how this architecture stands up against other architectures such as a Windows-based environment. One of the resounding reasons that users may prefer a Linux-based environment over a Windows-based environment is that Linux environments are free to users and organizations. This is undoubtedly a great benefit for financial reasons, but it goes further than that.
One of the greatest challenges that administrators encounter regarding paid license-based services is around license management. Often, administrators find themselves encountering issues around licenses falling out of support, license-related software bugs, and challenges around requesting licensing budget from decision-makers. All of these confounding factors result in many administrators relying on the free, flexible, and highly configurable Linux architecture model.
Hopefully, by this point, you've gained a better understanding of both Linux services and Linux server roles. As you move forward, consider diving into building a deep working knowledge of Linux services, server roles, and general Linux administration practices to help gain a deeper familiarity with Linux. Through the resounding feedback from IT professionals, having a strong background as a Linux practitioner will not only open more doors within one's career but will also provide a strong background in many of the critical responsibilities seen in day-to-day life as an IT administrator.