Korbin Brown

SSH server enabled and running on AlmaLinux

How to enable SSH on Almalinux

9 March 2021 by Korbin Brown

SSH is the primary method of remote access and administration on Linux systems. SSH is a client-server service providing secure, encrypted connections over a network connection. After installing AlmaLinux or migrating from CentOS to AlmaLinux, it will probably be one of the first things you want to configure.

In this guide, we’ll go over the step by step instructions to install and configure SSH on AlmaLinux. This will help you whether you just want to connect to remote systems via SSH or you want your own system to accept incoming connections as well.

In this tutorial you will learn:

How to install SSH
How to start and stop the SSH service
How to allow SSH through system firewall

SSH server enabled and running on AlmaLinux

How to reset password on AlmaLinux

9 March 2021 by Korbin Brown

After installing AlmaLinux or migrating from CentOS to AlmaLinux, most users will eventually run into the need to do some user account management, such as adding a new user account or resetting a password.

If you or one of the other users of an AlmaLinux system forgets the password to their account, there’s a simple way to reset the password from either command line or GUI. The same steps can also apply if it’s simply time to change your password or you want to force another user’s password to expire and change.

There are several scenarios that you might encounter that cause you to reset your password.

You need to change a normal user or the root account’s password
You want to force a user to change their password
You have forgotten the root account password

In this guide, we’ll be covering the step by step instructions for problems 1 and 2 mentioned above. If you need help resetting your system’s root password, see our other guide for recovering a root password on RHEL.

In this tutorial you will learn:

How to change user or root password via command line
How to change user password via GNOME GUI
How to force a user’s password to expire and be reset

Resetting a user password on AlmaLinux

How to add route on AlmaLinux

9 March 2021 by Korbin Brown

By default, when a Linux system tries to communicate with a network address, the computer will send the request to the default gateway. The default gateway is usually a router, which can take the system’s request and forward it to the next hop, wherever that may be.

This behavior can be overridden by adding one or more static routes to the Linux machine. Such a configuration can be desirable if the network has multiple networks and routers, and a user needs to instruct the computer which way to route certain traffic.

Red Hat based distributions, such as AlmaLinux, can use the nmcli command line utility to configure static routes, along with the ip route command and manual configuration of ifcfg files. Alternatively, you can use your installed desktop environment to apply the configuration. In this guide, we’ll go over the step by step instructions to add static routes on AlmaLinux through both command line and GUI methods. These instructions are applicable whether you’ve freshly installed AlmaLinux or have migrated from CentOS to AlmaLinux.

In this tutorial you will learn:

How to add a route via nmcli command
How to add a route via ip route command
How to add a route via ifcfg files
How to add a route via GNOME GUI

Adding a new static route in AlmaLinux

Allowing a port through the firewall on AlmaLinux

How to allow port through firewall on AlmaLinux

9 March 2021 by Korbin Brown

firewalld is the default firewall program that comes pre-installed on Red Hat Enterprise Linux and its derivative Linux distributions, such as AlmaLinux.

By default, the firewall is turned on, meaning that a very limited number of services are able to receive incoming traffic. This is a nice security feature, but it means that the user must be knowledgeable enough to configure the firewall whenever they install a new service on the system, like HTTPD or SSH for example. Otherwise, connections from the internet can’t reach these services.

Rather than disabling the firewall on AlmaLinux entirely, we can allow certain ports through the firewall, which lets incoming connections reach our services. In this guide, we’ll see how to allow a port through the firewall on AlmaLinux. Feel free to follow along whether you’ve freshly installed AlmaLinux or migrated from CentOS to AlmaLinux.

In this tutorial you will learn:

How to allow a port or service through the firewall on AlmaLinux
How to reload the firewall for changes to take effect
How to check what ports and services are open in the firewall
How to close a port after having it configured as open
Command examples for allowing the most common ports through firewall

Allowing a port through the firewall on AlmaLinux

How to disable SELinux on AlmaLinux

9 March 2021 by Korbin Brown

SELinux, which stands for Security Enhanced Linux, is an extra layer of security control built into Red Hat Enterprise Linux and its derivative Linux distributions, such as AlmaLinux. SELinux is enabled by default on the system, and would have to be manually disabled if a user doesn’t wish to use it.

Although SELinux can protect our system through access control for programs and system services, it’s not always necessary to have it enabled. Some users may even find that it interferes with certain programs they try to install. In this guide, we’ll go over the step by step instructions to disable SELinux on AlmaLinux, whether you’ve freshly installed AlmaLinux or migrated from CentOS to AlmaLinux.

In this tutorial you will learn:

How to check the status of SELinux
How to put SELinux in permissive mode
How to disable SELinux

Disabling SELinux on AlmaLinux

How to disable or enable the firewall on AlmaLinux

How to disable/enable firewall on AlmaLinux

4 March 2021 by Korbin Brown

firewalld is the firewall manager that comes pre-installed on AlmaLinux, whether you’ve freshly installed AlmaLinux or migrated from CentOS to AlmaLinux. By default, the firewall is turned on, meaning that a very limited number of services are able to receive incoming traffic.

This is a nice security feature, but it means that the user must be knowledgeable enough to configure the firewall whenever they install a new service on the system, like HTTPD or SSH for example. Otherwise, connections from the internet can’t reach these services.

In this guide, we’ll see how to disable or enable the firewall in AlmaLinux, along with checking the status of the firewall. These are good troubleshooting options when trying to determine if a firewall rule is blocking traffic to or from a particular service.

DID YOU KNOW?
firewalld is simply a front end for the system’s nftables (formerly iptables) firewall. This makes the firewall easier to interact with, but essentially firewalld just translates all our commands into corresponding nft commands.

In this tutorial you will learn:

How to check the firewall status on AlmaLinux
How to stop firewall on AlmaLinux
How to start firewall on AlmaLinux
How to permanently disable firewall on AlmaLinux
How to enable firewall to start after reboot

How to disable or enable the firewall on AlmaLinux

Changing the time zone via command line and GUI on AlmaLinux

How to set/change time zone on AlmaLinux

4 March 2021 by Korbin Brown

The objective of this guide is to show how to set the system time zone on AlmaLinux. This can be done from both GUI and command line, so we’ll be covering both methods in the following instructions.

Setting your system time and time zone is usually done when initially installing AlmaLinux or migrating from CentOS to AlmaLinux. If you skipped that step during installation, have switched time zones, or your system clock has drifted out of sync, we’ll help you get it fixed.

In this tutorial you will learn:

How to set time zone on AlmaLinux from GNOME GUI
How to set time zone on AlmaLinux from command line

Changing the time zone via command line and GUI on AlmaLinux

Docker running a container image on AlmaLinux

Install Docker on AlmaLinux

4 March 2021 by Korbin Brown

Docker is a tool that is used to run software in a container. It’s a great way for developers and users to worry less about compatibility with an operating system and dependencies because the contained software should run identically on any system.

If you’ve recently installed AlmaLinux or migrated from CentOS to AlmaLinux, you may be wondering how to get Docker up and running on the system. Unfortunately, Red Hat Enterprise Linux doesn’t offer native support for Docker, and neither does AlmaLinux, since it is a fork of RHEL. Instead, Red Hat pushes support for Podman, an alternative to Docker. This makes Docker a bit harder to install, but it’s still possible on AlmaLinux.

In this guide, we’ll show you how to install Docker on AlmaLinux and get started with installing containerized software. After Docker is installed, you can use it to install software packages much the same way you would use your distro’s package manager to download an app. The difference of using Docker is that everything is more automated, with compatibility and dependencies no longer being potential issues.

In this tutorial you will learn:

How to install Docker
How to run Docker without root
How to search for a Docker image
How to install a Docker image
How to run a Docker image
How to monitor Docker with various commands

Docker running a container image on AlmaLinux

CentOS vs CentOS Stream

4 March 2021 by Korbin Brown

Up until a late 2020 announcement from Red Hat, CentOS Linux had a longstanding reputation as a dependable and enterprise-class Linux distribution. And now, the main purpose of CentOS is shifting. Along with that comes a name change to CentOS Stream.

In this article, we’ll talk about this change of direction for CentOS, and what it means for the huge community of users and businesses that have relied on the distro for years. We’ll also see what’s next, as many users are left scrambling for a replacement so they can avoid switching to CentOS Stream.

How to add user on AlmaLinux

4 March 2021 by Korbin Brown

After installing AlmaLinux or migrating from CentOS to AlmaLinux, most users will eventually run into the need to do some user account management. This is especially true if you only have a root account on your system and need to setup one or more normal users.

In this guide, we’ll show you the step by step instructions to add a new user on an AlmaLinux system. This can be done through both GUI and command line. We’ll be covering both methods in this guide, so you can pick whichever option is most convenient for you.

In this tutorial you will learn:

How to add a new user on AlmaLinux from command line
How to add a new user on AlmaLinux from GNOME GUI

Adding a new user account on AlmaLinux

How to delete directory on Linux

24 February 2021 by Korbin Brown

Deleting a directory (also called folder) on Linux is a common task that every user will have to perform at some time or another. This can be done via any desktop environment that you have installed, or from command line with the rm command.

While this is a pretty basic function, there are some important caveats to keep in mind. In this guide, we’ll go over several examples of deleting a directory on Linux. Feel free to follow along on your own system in order to master the rm command and GUI process.

In this tutorial you will learn:

How to delete a directory via GUI
How to delete a directory via command line

How to delete a directory on Linux

How to use time command on Linux

24 February 2021 by Korbin Brown

The time command is a very simple, but useful command line utility in Linux. Essentially, you can think of it as a stopwatch built into the terminal, as it measures the amount of time it takes to execute a specified Linux command.

In this guide, we’ll show you how to use the time command through various examples, and teach you how to interpret its output. We’ll also show how to use GNU time, which is different than the time utility built into the Bash and zsh shells.

In this tutorial you will learn:

How to use time command
How to use GNU time
How to interpret the output of the time and GNU time commands

time command on Linux