Jeff Wilson 
The DNS_PROBE_FINISHED_NXDOMAIN is an issue related to the Domain Name System (DNS). It occurs when the DNS can not connect the website URL to the server IP address. When we enter the domain in our browser, the DNS fails to resolve the domain name. The NXDOMAIN stands for non-existing domain and the cause of this can be DNS misconfiguration, DNS propagation, Firewall, Internet Connection, etc.
Sometimes, Windows users experience an issue when accessing a website. When trying to access the website using your web browser, you might see the “Server IP address could not be found” message. Not to worry – there’s not much that could be wrong here. We’ll show you how to fix the “server IP address could not be found” error.
This tutorial is about the OOM killer and how it can impact our Linux operating system.
OOM killer is a shortcut to Out of Memory Killer and is a Linux component designed to prevent RAM exhaustion. The OOM Killer has one task, and that task is to check if there is enough available memory, and if there is not, then select a process to kill to free up some RAM. The situations with exhausted memory occur because the Linux kernel has over-allocated too much for its processes. In the following paragraphs, we will talk about memory over-allocation, the lifecycle of the OOM killer, how it selects which process should be killed, the OOM killer messages, etc.
In this guide, we will demonstrate how to install and configure a mail server on Ubuntu 24.04, as large and medium-sized companies can greatly benefit from having a private email server. By utilizing a mail server, it becomes feasible to monitor all email traffic closely. Additionally, the flexibility to customize settings enables the establishment of a clear and organized email service. While there are various options available for setting up a Linux email server, we will specifically concentrate on Postfix and Dovecot.
Cron is a widely used tool which is used to schedule tasks or so-called jobs on any Unix-like operating system. It can be set up to run the corn jobs daily, weekly, or monthly, but it can also be set up to run any given period or once only.
For example, you want to run a backup script during off-work hours. Using cron jobs, you can easily schedule the script to run at a specific time daily, every second day, weekly, or any other period.
When trying to access a website, you may get a 401 unauthorized error message. This error message not only makes things difficult for website visitors but can also make things difficult for website owners. If you are a website visitor, this error message means you cannot log in to or even view a website. You will not be able to enjoy the features on the website. In addition, for website owners, you will not be able to enter the admin dashboard of your own website.
Even though Error 401 is troublesome, you don’t need to worry. We will explain the cause and how to solve it. This article summarizes the 401 Unauthorized HTTP error code and provides instructions on troubleshooting procedures to address it in case you encounter this problem.
Because everything in Linux is treated as a file, using links adds flexibility to create mappings to certain files or directories. There are hard links and soft links. A symlink, also called a symbolic link, is a file that points to another file or directory on the server. Except for files and directories, the symlinks can point to pipes or even other symlinks, which creates symbolic link chains.
This tutorial will explain what Bash Shebang is and how to use the Shebang characters in Bash scripts on the Linux system.
Shebang is a sequence of two characters: a number sign (#) and an exclamation mark (!) that gives us the #! at the beginning of every script we need to write. Shebang is also known as hashbang, pound-bang, or hash-pling. It is always defined in the first line of the script and is ignored by the interpreter.
In the next paragraphs, we will show you how to use the Shebang with real examples. Let’s get started!