Explain DEBIAN_FRONTEND apt-get variable for Ubuntu / Debian

Can you explain DEBIAN_FRONTEND apt or apt-get variable? How and why I need to use this in Docker or shell scripts under a Debian and Ubuntu Linux?

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Ubuntu 20.04 LTS change hostname permanently

I am a brand-new Ubuntu Linux 20.04 LTS VM user. By default, my server name to 'localhost' during cloud installation, but now I would like to change the computer name to 'ubuntu-2004-nixcraft'. Can you tell me how do I remove the localhost and set it to ubuntu-2004-nixcraft on Ubuntu 20.04 Linux? How do I change the Ubuntu computer name from 'localhost' to 'ubuntu-2004-nixcraft'? Can you tell me more about Ubuntu Linux change hostname command?

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Linux Rename Multiple Files At a Shell Prompt

How do I rename multiple files at a shell prompt under a Linux or UNIX operating systems?

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Upgrade Ubuntu 18.04 to 20.04 LTS using command line

I need to upgrade the Ubuntu Linux version 18.04 LTS server to a 20.04 LTS server using the command line option. How do I upgrade Ubuntu 18.04 to 20.04?

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Protects Linux machines from accidental shutdowns/reboots with molly-guard

Oops! I did it again. I thought I was logged into my home server. Turns out I rebooted the db server. Another my not so favorite is typing 'shutdown -h 0' into the wrong terminal. I know a few people who have admitted to doing that here.

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Linux find Windows 10 OEM product key command

I removed and installed Ubuntu Linux 16.04 LTS on my development Lenovo laptop. However, I need to use my Windows 10 pro in KVM VM for running the accounting app. How do I find and print my embedded Windows 10 pro key from a Linux command line option? How can I retrieve Microsoft Windows 8 and 10 OEM product key from BIOS?

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Linux / Unix Rsync Copy Hidden Dot Files and Directories Only

How do I use the rsync tool to copy only the hidden files and directory (such as ~/.ssh/, ~/.foo, and so on) from /home/jobs directory to the /mnt/usb directory under Unix like operating system?

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Add a new user account with admin access on Linux

How do I add a user account with admin (sudo) access on Ubuntu or CentOS Linux cloud server? How can I add a new user with admin account level access in Linux?

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Alarm clock Set Timeout For A Shell Command

How can I run a command called foo, and have it timeout/abort after 10 seconds under GNU/Linux running bash shell or script? How do I run the command under an alarm clock?

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How to use/run bash aliases over ssh based session

I have set up a bash alias named file_repl. It works entirely when I log in using ssh command. However, my bash aliases are not running over ssh, for example:
$ ssh vivek@server1.cyberciti.biz file_replbash: file_repl: command not foundHow do I run bash shell aliases when I use ssh command?

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CentOS Linux 8.1 (1911) released and here is how to upgrade it

CentOS Linux 8.1 (1191) released. It is a Linux distribution derived from RHEL (Red Hat Enterprise Linux) 8.1 source code. CentOS was created when Red Hat stopped providing RHEL free. CentOS 8.1 gives complete control of its open-source software packages and is fully customized for research needs or for running a high-performance website without the need for license fees. Let us see what's new in CentOS 8.1 (1911) and how to upgrade existing CentOS 8.0.1905 server to 8.1.1911 using the command line.

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Dell XPS 13 Developer Edition 2020 Ubuntu Laptop Announced

Look like Dell listing to customer feedback. Dell XPS 13 Developer Edition is the ultimate Linux laptop for developers and Linux enthusiasts/power users. The Dell XPS 13 Developer Edition 2020 now supports 10th Gen Intel CPU and 32GB ram. This system comes pre-installed with Ubuntu Linux 18.04, but you can install any other distro.

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Helios64 Arm-Based Linux NAS announced

Helios64 is an upgraded version Helios4 of ARM-based NAS SBC (Single-board computer) for Linux. This NAS (Network Attached Storage) comes with 5 SATA 3.0 port, M.2 sata slot, LPDDR 4 ram, and hexacore SoC. Let us see some details about the Helios64 Arm-Based Linux NAS SBC, including pricing and hardware specs information.

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Linux rpm List Installed Packages Command

How do I list all installed packages using rpm command on CentOS/Suse/Fedora/RHEL/Scientific and Red Hat Enterprise Linux? Can you tell me the Linux command to list all rpm's installed on the server?

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Linux Find Out Maximum RAM Supported By Server / BIOS

How do I find out the maximum RAM supported by the Dell, HP, IBM, Oracle/Sun or Intel/AMD server on a Linux or Unix-like operating systems without rebooting the server or opening the server case (chassis)? How can I find find out maximum RAM supported by the Server BIOS and motherboard in Linux?

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How to configure Nginx with Let’s Encrypt on CentOS 8

How do I secure my Nginx web server with Let's Encrypt free ssl certificate on my CentOS 8 server? How to set up and configure Nginx with Let's Encrypt on CentOS 8?

The post How to configure Nginx with Let’s Encrypt on CentOS 8 appeared first on nixCraft.

Linux exit from lxc-console keyboard shortcut

I am using Debian Linux server with Linux Containers (lxc). How do I disconnect and exit from an lxc-console to a shell prompt without closing ssh session?

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Ubuntu Linux Change Hostname (computer name)

How do I change the Ubuntu computer name from 'ubuntu' to 'AvlinStar'? Can you tell me more about Ubuntu Linux change hostname command?

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How to upgrade Alpine Linux 3.10 to 3.11

I am using Alpine Linux v3.9 or v3.10 with my LXD server. How do I upgrade Alpine Linux v3.9 to Alpine Linux v3.11? How can I upgrade Alpine Linux v3.10 to Alpine Linux v3.11?

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Remove grep command while grepping using ps command

I use ps command to find out all running process on my Linux and Unix system. The ps command shows information about a selection of the active processes on shell. You may also pipe out ps command output through grep command to pick up desired output. Let us see how to prevent 'grep' from showing up in ps results?

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How do I count how many processes are running in Linux?

How do I see how many processes are running in Linux? How can count all running processes in Linux?

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Kubuntu Linux Focus Laptop Announced

Kubuntu is a free and open-source version based upon Ubuntu Linux. Kubuntu flavor uses KDE instead of GNOME desktop. Now, the Kubuntu project announced the first authorized laptop called Kubuntu Focus in collaboration with MindShareManagement Inc, and Tuxedo Computers. Let us see technical specs and other information.

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Grep From Files and Display the File Name On Linux or Unix System

How do I grep from a number of files and display the file name only? How do I force the grep command to display the filename before the matching lines in its output?

The post Grep From Files and Display the File Name On Linux or Unix System appeared first on nixCraft.

Remove Santa Hat in VLC Player Permanently

How do I remove Santa Hat in VLC media player that displayed during Christmas time during 18th December to 1st January?

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Python Get Today's Current Date and Time

How do I find out the current date and time in Python? What is the module or function I need to use to get current time or date in Python programming language? How can I get today's date and current date and time in Python in different formats using strftime() method?

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CentOS 8 update installed packages for security

I need to update installed packages for security on CentOS 8.x (CentOS Enterprise Linux) server. How can I update my CentOS 8.x system using yum command?

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How to install tar on RHEL/CentOS 6/7/8 using yum

I am trying to extract a file using 'tar xvf file.tar.gz' syntax, but I am getting an error:
bash: tar: command not found
How do I fix this problem? How can I install tar on a CentOS/RHEL version 8, 7 or 6 desktop using yum command?

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How to Install PHP 7.x on CentOS 8 For Nginx

How do I install PHP 7.x on CentOS 8 Linux server along with Nginx? How can I install the latest version of PHP 7.4 on CentOS Enterprise Linux 8 server?

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killersheep – Silly game for Vim version 8.2

Vim is my favorite text editor and version 8.2 released. The new version includes support for popup windows and text properties. Popup windows can be used for many purposes. For example, a list of choices can be displayed, where the user selects an entry with keys or with the mouse. There is also a new vim game released named as killersheep to show you new capabilities of Vim. Let us see how to install and play killersheep.

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Gracefully Restart Nginx Web Server After Changes Made In a Config File

I know how to gracefully restart Apache web server under Unix like operating system. I made changes to nginx.conf. How do I gracefully restart Nginx web server? How do I make changes in a Nginx server config file to take effect without restarting the Nginx server itself without interrupting users' current session?

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How to install htop on OpenSUSE Linux using zypper

I am a new sysadmin of OpenSUSE Linux operating system. How do I install htop on OpenSUSE using the zypper command?

The post How to install htop on OpenSUSE Linux using zypper appeared first on nixCraft.

Linux check the physical health of a USB stick [ Flash drive ]

How do I check the physical health of a USB stick in Linux operating systems? How do I check USB flash drive in Linux? Can you tell me Linux command to test and detect bad sector in USB flash memory or pen drives?

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BASH Shell Test If a File Is Writable or Not

How can you test if a file is writable under UNIX / Linux bash shell scripting and programming language?

The post BASH Shell Test If a File Is Writable or Not appeared first on nixCraft.

How to see Time-To-Live (TTL) for a DNS record

How do I see Time-To-Live (TTL) for a DNS record using Linux, macOS, *BSD, or Unix-like systems command line option? How do I find my DNS TTL?

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How to test and validate DNSSEC using dig command line

How do I test and validate DNSSEC using the dig command line under Linux, macOS, *BSD, and Unix-like systems?

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How to add bash auto completion in CentOS 8 Linux

I set up a new cloud server, but my auto-completion of bash shell commands are not working. How do I enable autocomplete feature in CentOS 8 (CentOS Enterprise Linux 8)? How do I write simple bash completion code in CentOS 8?

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How to set rsync speed limit from eating all bandwidth

The rsync command is eating all my bandwidth from a backup script and generating tons of I/O. How do I set a limit for file transfer speed of rsync command on Linux or Unix-like system? How can I keep my rsync script from using all of my bandwidth?

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How to set rsync speed limit from eating all bandwidth

The rsync command is eating all my bandwidth from a backup script and generating tons of I/O. How do I set a limit for file transfer speed of rsync command on Linux or Unix-like system? How can I keep my rsync script from using all of my bandwidth?

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How To Set up OpenVPN Server In 5 Minutes on Ubuntu Linux

{Updated} I am a new Ubuntu Linux server user. How do I setup an OpenVPN Server on Ubuntu Linux version 14.04/19.10, or 16.04/18.04 LTS server to shield my browsing activity from bad guys on public Wi-Fi, and more?

The post How To Set up OpenVPN Server In 5 Minutes on Ubuntu Linux appeared first on nixCraft.

Add / Create a Sudo User on CentOS Linux 8

How do I add / create a sudo user on CentOS Linux 8 using the command line?

The post Add / Create a Sudo User on CentOS Linux 8 appeared first on nixCraft.

Vi / Vim Save And Quit The Editor Command

{Updated} I am a new vi / vim text editor user. How do I quit the vi editor and save my changes under a Linux or Unix like operating systems? Can you tell me command to save and quit file in vim?

The post Vi / Vim Save And Quit The Editor Command appeared first on nixCraft.

Understanding /etc/passwd File Format

Can you explain /etc/passwd file format for Linux and Unix-like operating systems?

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How to install and use Nginx on OpenSUSE Linux server

How do I install and configure the latest version of Nginx web server on OpenSUSE Linux server using the CLI and host a static site?

The post How to install and use Nginx on OpenSUSE Linux server appeared first on nixCraft.

How to add or mount directory in LXD (Linux container)

I have two LXD containers running. One is for Nginx, and another is for processing data. I need to share data between two containers. How do I add or mount a shared directory between two?

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Debian / Ubuntu Linux Delete Old Kernel Images Command

I am a new Ubuntu Linux user and noticed that old kernel still exists in my system. Why doesn't Ubuntu remove old kernels automatically? How do I delete old unused kernel images to free disk space. How to remove unused old kernel images on Ubuntu Linux safely?

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Configure Nginx to use TLS 1.2 and 1.3 only

How do I enable and configure TLS 1.2 and 1.3 only in Nginx web server?

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How to set up a firewall using FirewallD on OpenSUSE Linux

I am a new OpenSUSE Linux 15.x sysadmin. How do I set up a firewall using FirwallD on OpenSUSE Linux 15.1?

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How to generate RSS 2.0 feed quickly using Python

I wanted to generate RSS 2.0 feeds in Python. Nothing fancy but for certain tasks I needed it something that is quick and just works out of the box. I found rfeed. It is a library to generate RSS 2.0 feeds in Python. It is in my opinion straightforward to use. This post explains how to generate RSS 2.0 feed quickly using Python.

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How to check and list installed packages in CentOS Linux

How do I check installed packages in CentOS Linux version 6.x/7.x/8.x? How can I List installed packages on CentOS Enterprise Linux server?

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[How to] Linux Change or Rename User Name and UID

How do I change user name (rename user name) or UID under a Linux operating system using command line tools? How do I change or rename username in Linux?

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