Application Servers Overview

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Video Transcript

This module is all about application servers. So, before we begin talking about them in-depth, we should first discuss what an application server actually is.

In this class, I’ll be referring to an application server as any server that runs an enterprise application. So far, in this course we’ve dealt with setting up workstations, centralized authentication systems, network services, and cloud resources, but most of those are just the infrastructure for our enterprise. Most of the activity in our organization will happen on top of that infrastructure in a variety of application servers. They handle the backend processing and storage of data, as well as the frontend interface that our users will see, either on a website, mobile application, or custom software tool. In general, application servers, are the always on, always available resources that our infrastructure provides to our users.

There are many different types of application servers that your organization may use. These could include web servers such as Apache or IIS, database servers such as MySQL or Microsoft SQL Server, email servers, and even some file servers. Those servers could also run specialized application such as customer relationship management or CRM, inventory, accounting, and more. In this course, we’ll primarily be dealing with web servers, file servers, and database servers, as they are most commonly used in a variety of enterprises.

One of the major tasks that any system administrator may face is to help your organization evaluate and choose new software. The choice of enterprise software is a very important decision, and can have a major impact on your organization’s budget, flexibility, and success in the future. So, in this video, I’ll discuss some considerations you should have in mind if you are ever asked to evaluate software for your organization.

The first step is to perform an evaluation of the software packages available for your needs, before you ever download or install them. Some things you might look at in this phase are the source of the software itself: is it a reputable company, an open-source project, or an unknown entity. Likewise, you could look at the available support offerings, knowledgebase, and user community around the software. If the community is active and the support documentation is well written, it is generally a very good sign. You might also look at the company’s history and coding practices if you can find any information about either of those. If the company has a history of good software, or, conversely a history of major flaws and bugs, that should weigh into your decision as well. Depending on your needs, you might also explore options for extending the software and integrating it into your existing infrastructure. Finally, it’s always a good idea to read some reviews and seek recommendations from others. If your organization works in a unique field, it might be worth contacting some of your peers to see what they are using and what their experience has been. In many cases, they can direct you to the best option available, or let you avoid the mistakes they’ve made along the way. And all of this comes before you’ve even looked at the software itself!

Once you have a few candidates that you’d like to test, you should go through the process of installing or using each one. As you do so, you’ll want to make a note of any other software or tools that are needed to work with the application you are reviewing. You’ll also be on the lookout for system requirements, such as storage, RAM and CPU usage. In addition, you should look at how easy it is to get data in and out of the system. One of the major frustrations with enterprise software is “vendor lock-in,” which happens when all of your data is tied to a particular software program or vendor, and there is no easy way to move to a new system. Next, you’ll want to consider how easy it was to configure the software. Does it have all the options you need, or are there parts of the system that are difficult to work with for you as an administrator, or possibly for your users. Finally, as you work with the software, you’ll definitely want to use tools such as Wireshark to monitor any network traffic on your systems. While it is rare, some applications can have major security flaws or even be compromised before installation, so you should always be on the lookout for unusual network traffic when evaluating new software.

Lastly, you’ll need to extensively test the software for usability with your users and customers. Even if the software itself is high quality, if your users are unable to use it effectively, it could be worse than not having any software at all. As you work with a group of users to beta test the system, you’ll want to monitor many aspects of how the system performs, such as the system load and load balancing needed. You should also continue to monitor the network traffic, and ensure that any data sent across the network is properly encrypted. Remember our example from Lab 3 with Apache authentication - just because it is unreadable doesn’t mean that it is properly encrypted, so you may have to consult the documentation or a security expert if you aren’t sure.

In addition, you may also want to look at how easy it is to deploy updates to the system. Does it require a large amount of downtime, or is it relatively seamless? You could also look at features such as logging and accountability. Are you able to tell which users are accessing the system, and what they are doing? It could help you diagnose problems, but also detect when users are acting maliciously. In many cases, security issues are the result of insider threats, so having a good idea of what your users are doing is very important. Finally, you should always evaluate the accessibility of the software. Does it work well with assistive devices such as a screen reader or alternative input devices? Would colorblind users have issues interacting with the software? Sometimes this can be as simple as having red and green buttons or icons with no text on them - a colorblind user would not be able to tell the difference between them.

Of course, there are many, many more things you should consider when choosing software for any organization. My hope is that this will give you at least some idea of what that process looks like. The rest of this module will deal primarily with how to configure and work with a variety of application servers, including file servers, web servers, and database servers.