php_admin_value and php_value are directives used in PHP-FPM (FastCGI Process Manager) configuration, often seen in context with web server setups like Apache or Nginx. They are used to set values for PHP's configuration directives e.g. in a PHP-FPM pool file or in the Apache server configuration. This is an alternative to changing PHP settings in ... Read more
What is the PATH variable? In Linux, executable files reside in many different directories. But you may have noticed that you do not provide a directory path while running your common commands. So you might wonder, how does the Linux system know where the relative executable is. That's where the PATH variable comes in, the ... Read more
In Postfix configuration, particularly on Debian and Ubuntu systems, you might come across terms like "submission" and "submissions" when looking into the Postfix /etc/postfix/master.cf file. This article explains the differences and use cases for both ports. Postfix Submission Port 587 This is the standard port for email submission as defined by the Internet Message Access ... Read more
pSome internet access providers have port 25 disabled in their routers to prevent spam. If you run your own email server in a data center, you might have to enable the submission port (587) in postfix to be able to send emails from your local email client to your own mail server. Enable Submission Port ... Read more
The world of Linux is diverse, Linux distributions using different package management systems. RPM (Red Hat Package Manager) and Debian's DEB are two of the most common package formats. Occasionally, users of Debian-based systems might need to install software that's only available in the RPM format. This guide covers converting RPM packages to DEB format, ... Read more
Linux offers a powerful tool for file transfer on the shell: the FTP command. FTP (File Transfer Protocol) is a standard network protocol for transferring files between a client and server on a computer network. This article shows how to use the Linux FTP command to upload and download files using the Linux command-line interface, ... Read more
The Nginx web server has a max. body size limit of 1 MB for requests as default. This might be too low for file uploads in scripts and you will see the following error message when you try to upload a file: 413 Request Entity Too Large The configuration variable for this option is "client_max_body_size" ... Read more
To restart a Docker container, you can use the docker restart command. This command stops and then starts the specified container. Here's a step-by-step guide on how to restart a Docker container, along with command examples: List Running Docker Containers As the first step, you need to identify the container you want to restart. To ... Read more
The PDF file format is the conventional document format for sharing text files over the internet. Whether it's for professional, school, or informal use, PDF files are a convenient way of sharing information. One thing that stands out with PDF format is that the content of the files remains unchanged regardless of the operating system ... Read more
Winmail.dat files are a unique file format utilized primarily by Microsoft Outlook. These files serve as containers for attachments sent through emails formatted in rich-text. This format can cause compatibility issues, particularly when users of non-Microsoft email clients, such as those on Linux systems, receive attachments. What is a Winmail.dat File? When an Outlook user ... Read more