Linux

Did you know? You can turn off the banner in Linux or Unix using a particular file. When you log in using ssh or other methods, you will find tons of information on the screen. Here is how my FreeBSD home server login looks:

FreeBSD login banner

Default motd with my hardware and other info

The first one is /etc/motd, and the second is the output of neofetch called from ~/.profile file. And my Ubuntu Linux box showing stuff too when I login using the ssh command:
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The du (disk usage) command summarizes directory trees’ sizes, including all of their contents and individual files’ sizes on Linux and Unix-like systems such as macOS. It helps track down space hogs. In other words, we can list directories and files that consume large amounts of space on a hard disk drive. Let us see the ncdu command, a curses-based version of the well-known du command.
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The Debian GNU/Linux project has released an updated version of its stable Linux distribution Debian 10 (“buster”). You must upgrade to get corrections for security problem as this version made a few adjustments for the severe issue found in Debian version 10.8. Debian is a Unix-like (Linux distro) operating system and a distribution of Free Software. It is mainly maintained and updated through the work of many users who volunteer their time and effort. The Debian Project was first announced in 1993 by Ian Murdock.
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We can easily add a key file to LUKS disk encryption on Linux when running the cryptsetup command. A key file is used as the passphrase to unlock an encrypted volume. The passphrase allows Linux users to open encrypted disks utilizing a keyboard or over an ssh-based session. There are different types of key files we can add and enable LUKS disk encryption on Linux as per our needs:

  1. Passphrase keyfile – It is a key file holding a simple passphrase.
  2. Random text keyfile – This is a key file comprising a block of random characters which is much more resistant to dictionary attacks than a simple passphrase-based key file.
  3. Binary keyfile – We can defile an image, video, or any other static binary file as key file for LUKS. It makes it harder to identify as a key file. It would look like a regular image file or video clip to the attacker instead of a random text keyfile.

Let us see how to enable LUKS disk encryption with a key file.
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Dart is easy to use BSD licensed programming language to build mobile, desktop, server, and web apps. Google creates and maintains the Dart ecosystem. It follows C-style syntax. We can compile code either to the native platform or JavaScript. Flutter allows building iOS/Android mobile and desktop/web apps from a single code base. Let us see how to install Dart programming language on a Debian or Ubuntu Linux and set vim as IDE.
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Despite some severe bugs in sudo, it remains the defacto tool to gain root shell or run command as another user on Linux, macOS, and Unix-like systems. The sudo command allows the system administrator to grant an individual user access to unprivileged commands. For instance, I can give developers the ability to restart the Apache webserver or PHP/Python process on a Linux server. Let us see how to remind developers and unprivileged users about the power of sudo for fun and profit. In this quick tip, I will show you how to add some spice to your sudo session with a lecture file on Linux or Unix.
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