Archive for the 'Server Configuration' Category


How to Add/Remove Yum Repositories

Red Hat Enterprise Linux, CentOS, Fedora and other Linux distributions based on RHEL all use YUM as a package management system to install, remove, and update software. Each distribution has its own main repository, but you can also install or remove third-party repositories whenever you like.
To add a YUM repository, type as root:
yum-config-manager –add-repo repository_url
For […]

How to Add and Remove APT Repositories

Ubuntu based Linux distributions rely on a program called APT to handle package management. Using the command “apt-get”, you can install, remove and update other programs. The packages installed with APT are determined by software repositories, and while every Linux distribution has default repositories, you can also add or remove third-party sources.
To add a Personal […]

Understanding Systemd and How to Use It: Part 2

In part one, you learned a little about what systemd is and which Linux distributions plan to use it. In part 2, you will learn how to use systemd to start and stop services. We will use Red Hat Enterprise Linux, CentOS and Fedora in the explanation, but most of it will apply to other […]

Understanding Systemd and How to Use It: Part 1

Systemd has gradually made a name for itself in the Linux world and is or will eventually be the default service management system for a number of major Linux distributions. Those accustomed to the old init systems will not find Systemd to be horribly complex, but it does feature some significantly different approaches to service […]

Send System Messages to Server Users

If your server has multiple users, you might want an easy way to send messages to them and make sure they receive them. The best way to do that is to send it right in the console. One tool you can use to do just that is “wall”. With it, you can send messages […]

What is a Journaling File system

As we discussed in a previous post, Linux servers offer many different types of file systems, and every other server operating system also offers a choice of file systems. One type of file system you might encounter is called a journaling file system. What is it and how does it differ from a standard Linux […]

Linux/Unix Terms You Should Know: Part 3

Part of the learning curve of a new Linux server is learning all of the terminology. You might not be familiar with some of them even if you have experiencing working on other operating systems. In part 3, we will look at some more of these terms.
daemon – This is a program that is often […]

Linux/Unix Terms You Should Know: Part 2

In part one, we looked at some of the important terms a new system administrator should know when starting work on a Linux server. These next terms are equally important and will help you along the way as you begin to learn more about your server.
man – This command, short for manual, gives you […]

Common Linux Terms Every SysAdmin Should Know: Part 1

A large percentage of the world’s servers run Linux, so it is a good idea to know some of the common terms you might encounter while using it. The following terms are a good starting point.
Command Line Interface (CLI) – On the server end, this is the main method of interfacing you will use to […]

How to Manage Linux Kernel Modules

Linux is the kernel for a variety of operating systems that power many of the world’s servers. Although the operating systems themselves are often commonly called Linux, the actual term refers specifically to this kernel and all of its parts. In addition to the components that are compiled into the kernel, Linux also supports modules […]

Write a Basic Bash Script to Simplify Server Operations

Linux comes with a very powerful tool built into it. It is called the shell. Bash is one version of the shell that is very popular with Linux distributions. If you can learn even basic Bash scripting, you can simplify and automate a lot of tasks you would normally have to manually perform on your […]

Tweaking Linux Server Swappiness for Increased Performance

Swappiness might sound silly, but it is actually a very useful parameter in the Linux kernel that determines how aggressively the kernel will use the swap partition. Linux is usually already well-optimized to use very little swap when physical memory is available. With the swappiness setting, you can increase or decrease this usage.
The default setting […]

3 Things Ways to Troubleshoot BEFORE Rebooting Your Server

If you have grown up using Microsoft Windows on your desktop or laptop, you are probably accustomed to the universal solution to most problems: reboot. When your screen freezes, reboot. If your system gets slow, reboot. That is the standard solution that even tech experts often dish out to common users. As a server administrator, […]

How to Add Storage to Your Linux Server

The time may come when you need to add additional storage to your Linux dedicated server. This might be to install a solid state drive, create new databases, back up data, expand your websites or even to add new virtual machines. Regardless of the reason, you would essentially use the same method to make Linux […]

Monitor Your Apache Load and Stats with mod_status

Apache HTTP Server is very extensible, allowing users to easily add new modules and thus new features and functionality. One such module that is helpful for monitoring your Apache web server is mod_status. mod_status keeps track of your web server’s load and displays it along with current httpd connections in a web-based interface.
mod_status displays a […]

Better Server Hosting Network Naming Schemes

It might be fun to name your networked servers something like “hiveship1” and “hiveship2”, but even if you do have some fun with it, you should still make sure you have a good naming system and stick to it. What follows are a few tips for server and network naming.
Hostname (also A record) – This […]

Some Benefits of FUSE on a Linux Server

FUSE stands for Filesystem in Userspace. As the name implies, it allows a user with limited privileges to create a functional filesystem without requiring root (administrative) privileges. Because the filesystems exist in userspace, they are technically virtual filesystems. They, nevertheless, function as though they are not. Does FUSE have any use on a […]

How to Create and Change Linux System Passwords

Server and website security seems to be in the headlines often lately with news of government surveillance and the heartbleed exploit in SSL. More than ever, it is important that you have a strong password. If you need to change your password on your Linux dedicated server or virtual private server, this guide should help […]

3 Ways to Enable and Disable Linux Services

Linux services or daemons are programs that typically start when the system boots and remain running in the background until the system shuts down. What follows are three distinct ways to manage services RHEL and CentOS servers.
1. chkconfig – You can use this simple command to show current services, enable them, disable them, […]

Working with Symbolic Links in Linux / Unix

In many cases, you may find yourself needing a particular file or directory in one location while it is actually stored in another. One solution to this in Linux and Unix operating systems is linking. There are two types of links: hard links and symbolic links.
Hard links are always associated with a specific piece of […]

Increase Server Security by Restricting Cron Jobs

Cron is one of the outstanding features in Linux and Unix-like operating systems that many system administrators love. It provides a full range of automation capabilities by allowing admins to schedule programs, scripts or other processes for any time of any day. Allowing other users to do this, however, can pose a security risk. Therefore, […]

How to Manage Linux Server Timezone Settings

Setting your date and time correctly on your Linux server is very important. Your server logs and other important information will all reflect the timezone of your server. In most cases, you will want to set your server’s time to match your own local time, but if your server is remote or hosting sites for […]

Setup and Configure CentOS Server Part 2

In part one, we began by changing the root password and then creating an account that will be able to escalate to root privileges when needed. Now, you need to make sure that only that user can become root and not anyone else.
The easiest way to do this is to use the “wheel” group. You […]

Setup and Configure CentOS Server Part 1

CentOS is essentially a free implementation of the open source code from Red Hat Enterprise Linux. Logos and other trademarks aside, CentOS is RHEL at its core without the licensing fees. As such, CentOS has become very popular among server administrators as an ideal Linux server solution. This brief tutorial will explain how to get […]

Using Fdisk to View Partition and Disk Information

If you ever need information about your attached media, whether it is a hard disk, solid state drive or something else, you can use fdisk to view them. It is quick, easy and can give you a lot of information.
To view currently attached disks, run this command as root:
fdisk -l
(That is a […]

Monitor System Services with Webmin

A dedicated server typically runs several background services or daemons. These may include but are not limited to your web server, database server, and mail server. All of these services need to be running 24/7 to keep them available for your users. When one of the services goes down, you need to know. Webmin has […]

5 Dumb Mistakes to Avoid with a Dedicated Server

This list is essentially useless. It is useless because no one would actually do the things on the list. Right? I joke of course, but these mistakes are ones you should definitely avoid. Some may seem like common knowledge, but they still happen far too often.
1. Using “password” as a password – For that […]

Storing Web Cache on a RAM Disk: Part Two

In part one, you learned how to create a basic RAM disk and how to make it permanent by creating an entry in /etc/fstab. In this section, you will learn how to configure your Apache to send certain files to your RAM drive.
In this example, we will only send images to the RAM drive. Special […]

Storing Web Cache on a RAM Disk: Part One

One way to speed up your web server is to cache frequently accessed pages and content. This is much faster because dynamic pages do not have to be recreated every time someone accesses them. Instead, the cached HTML files are loaded at a much faster rate. Using a RAM disk, you can make that caching […]

How Low Can I Set My DNS TTL?

TTL refers to Time To Live for a DNS server. You may find that your server’s default TTL is quite long, perhaps even 48 hours. This means that any changes to DNS zone files will take up to 48 hours to propagate to users. Because that can be very inconvenient when you want to change […]