Linux is a multi user operating system, meaning that it supports having multiple simultaneous user accounts. Some Linux systems may have a few different accounts, and others could have hundreds, depending on the purpose of the system. Switching between user accounts is a common task for Linux administrators who are in charge of user account management, as it allows them to test permissions or troubleshoot problems.
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How to switch to root on Linux
Linux users will inevitably need to log into the root account, or use administrator privileges, quite frequently. Tasks like installing or removing software, configuring system settings, adjusting file permissions, and many others usually require access to the root user account in order to perform. The root account can be accessed either by logging directly into the account, or by using the sudo Linux command to temporarily access root and execute a command with administrator privileges. In this tutorial, we will show you how to change to the root account on a Linux system, and how to use sudo to execute commands with root privileges.
How to Create and Manage a Pod in Kubernetes
A pod is the lowest and most basic container deployment and management unit in Kubernetes. Pods are a logical host for one or more containers that are connected through the localhost interface and share the same network namespace. When using Kubernetes, you will inevitably be creating pods when getting your applications up and running, and then managing your pods to make sure that your hosted applications are running as expected.
kubectl command examples (cheat sheet)
The kubectl command is the primary way of interacting with your Kubernetes cluster. It is safe to say that Linux administrators will be using the command on a constant basis when they are in charge of a Kubernetes environment. However, due to the sheer amount of command options available, it can be intimidating for newcomers and tricky to learn. Even longtime users may forget a command every once in a while and that is why we have created this tutorial full of kubectl command examples.
How to Manage Kubernetes Clusters With kubectl
The kubectl command is how administrators interact with and manage a Kubernetes cluster on a Linux system. It is an essential command line tool that works with all Kubernetes cluster envrionments like Amazon Web Services, Google Cloud Platform, or a cluster on your own hardware (e.g., kubeadm). Managing Kubernetes clusters at scale can be a challenge at first, but mastering the kubectl command will make it much easier.
How to disconnect from SSH connection
The SSH protocol in Linux is used to manage remote systems. It works by allowing you to securely log in to a remote device, which could be another Linux system, firewall, router, etc. When you are finished with your remote administration, it will be time to disconnect from the SSH connection. In this tutorial, you will see various ways to disconnect from an SSH connection on a Linux system. You will also learn the escape characters to exit from an SSH session, which comes in handy if you encounter a hung system that you have an SSH connection into and need to return to your local terminal.
Who Linux command: Explained
who is a very basic Linux command that is easy to learn and frequently comes in handy for Linux system administrators. It is a good way to see what users are logged into the system and information about each session. In this tutorial, we will explain how to use the who command on a Linux system, and go over all of its command line options. Follow along with our examples and you will quickly master this command and understand which situations it is most useful in.
Fixing the ‘Invalid Argument’ Error on Linux
If you have ever executed a Linux command in your system terminal and encountered the Invalid Argument error, there could be several causes. It usually indicates that an unrecognized argument has been specified, your current user does not have the proper file permissions on the file or directory, or the file is no longer accessible. There are also other potential causes and several methods we can employ to help resolve the error. In this tutorial, we will show you how to fix the Invalid Argument error on a Linux system.
Solving the ‘Command Not Found’ Error on Linux
While using the terminal of your Linux system, you will receive the Command Not Found error whenever a command you are entering is not accessible. In most cases, this could be due to a simple typo, or it could mean that you do not have the command installed yet. It could also indicate that the command is just missing from your system’s PATH environment variable, which is another easy thing to fix.
How to improve and debug your shell scripts with ShellCheck
ShellCheck is a free and open source static analysis tool which can be used to check and improve shell scripts. It is able to highlight both common and edge-case errors, and suggest the appropriate fixes. ShellCheck can be used as an online or system utility, but can also be integrated as a linter in various text editors.
How to fix: user not in sudoers file error
The purpose of this tutorial is to show how to fix the RHEL7 User Not In Sudoers File Error on all major Linux distributions. When trying to execute Linux commands with root privileges via the sudo command, you will receive an error message if the current user is not in the sudoers file. This is a security feature on Linux systems to stop ordinary users from esclating their commands to administrator privileges.
Troubleshooting the Application not found error in Flatpak
The Application not found error may occur in Flatpak on your Linux system for a variety of reasons. This typically happens when the application you are trying to open is not actually installed, or if the installation has been damaged through moving system files or some other means. In this tutorial, we will look at several ways to troubleshoot the Application not found error in Flatpak.