How to set up a firewall using FirewallD on CentOS 8

I am a new CentOS Enterprise Linux 8 sysadmin. How do I set up a firewall using FirwallD on CentOS 8?

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Linux run a command with a time limit (timeout)

I want to start command called foo, and kill it if still running after given DURATION in seconds. How do I run a command a time Limit on Linux? How do I run a Linux command, and have it timeout (abort) after N seconds?

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How To Protect SSH With Fail2Ban on CentOS 8

My ssh log file shows too many password failures. Random IP address trying to brute force my sshd server running on CentOS 8 server. How do I protect ssh with fail2ban on CentOS 8 Linux server? How do I install Fail2Ban on CentOS 8?

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How To Enable and Install EPEL Repo on CentOS 8.x

How do I install the extra repositories such as Fedora EPEL repo on a CentOS Enterprise Linux server version 8.x? How to enable EPEL repo on CentOS 8.x?

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How to install curl on Debian Linux 10/9/8

I am a new Debian Linux 10 or 9 user. I switched from Windows server and I trying to run the curl command from a shell script but getting the following error:
bash: curl: command not found
How do I fix this on a Debian Linux version 10 or 9/8?

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CentOS 8 Change Hostname (computer name) command

I am a new CentOS 8 Linux user and setup a server. They setup my server name to 'li2025-143' during deployment but now I would like to change the computer name to something else. How can I remove old name and set it to 'nixcraft-centos8' on CentOS Enterprise Linux? Can you tell me how do I change the CentOS 8 computer name? How do I assign a static hostname to server running CentOS 8?

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CentOS Linux 8 released: New Features and Download

CentOS Linux 8 released. It is a Linux distro derived from RHEL 8. CentOS was created when Red Hat stopped providing RHEL free. These days CentOS mostly used on servers, HPC, and desktop. CentOS is a high-quality Linux distribution. It 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.

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How to add users on FreeBSD using adduser or pw

I am a new FreeBSD system administrator. How do I add users on FreeBSD Unix operating systems using command line?

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How to display line number in vim

How do I display line numbers in vim running on Linux or Unix-like operating systems?

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FreeBSD Install sudo Command To Execute Commands

How do I install sudo command under a FreeBSD 9.x/10.x/11.x/12.x system?

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Amazon Linux AMI update installed packages for security

I would like to update installed packages for security on Amazon Linux AMI server running in the cloud. How can I update my Amazon Linux AMI system using yum command?

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SUSE 15 update installed packages for security

Iwould like to update installed packages for security on SUSE 15 (SUSE Linux Enterprise Server) server. How can I update my SUSE 15 system using zypper command?

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OpenBSD Install BASH Shell Package Command

How do I install BASH shell package under OpenBSD operating system? How do I set bash as a default login shell under OpenBSD?

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CentOS Linux 7.7 released and here is how to update it

The CentOS Linux project has released an updated version of its stable Linux distribution CentOS Linux 7.7. You must upgrade to get corrections for security problem as this version made a few adjustments for the severe issue found in CentOS 7.6. CentOS is a Linux distro that is mainly maintained and updated through the work of many users who volunteer their time and effort. It is based upon RHEL 7.7 upstream source code.

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RHEL 8 update installed packages for security

I would like to update installed packages for security on RHEL 8.x (Red Hat Enterprise Linux) server. How can I update my RHEL 8.x system using yum command?

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Linux Kernel 5.3 released and here is how to install it

Linux kernel version 5.3 released. This version includes many improvements including support for AMD Navi GPU, support for new IPv4 addresses in the 0.0.0.0/8 range, the lightweight hypervisor ACRN for embedded IoT devices and much more.

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How to install htop on FreeBSD

I am a new user of FreeBSD operating system. How do I install htop on FreeBSD using the pkg command?

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How to use the oathtool Linux command line for 2 step verification (2FA) code generation without any third-party apps

{Updated} I do not wish to use Google Authenticator or Authy app that generates 2 step verification (2FA) codes on my iOS/Android phone. Is there any way I can produce 2FA codes from Linux command line for popular sites such as Gmail, Twitter, Facebook, Amazon and more?

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FreeBSD Applying Security Updates Using pkg/freebsd-update

I am a new FreeBSD developer and user. I have root access to my VM running in AWS cloud. How do I update packages and apply security upgrades on FreeBSD? What is the procedure for applying security updates on FreeBSD?

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How to install Spotify application on Linux

How do I install Spotify application on Linux desktop to stream music?

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How to install Spotify application on Linux

How do I install Spotify application on Linux desktop to stream music?

The post How to install Spotify application on Linux appeared first on nixCraft.

In comics: Linux celebrates 28th birthday

On 26 August 1991, Linus Torvalds announced hobby project that was supposed to better than Minix operating systems. He said I am doing a free operating system. Just a hobby and won't be big or professional like GNU. Linux turns 28 years old, and we are going to celebrate Linux's birthday by sharing comics in pop culture that made it even more popular.

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Dell announces new Linux XPS 13 developer edition 7390 laptop

Dell recently announced the new XPS 13 developer edition powered by Ubuntu Linux and Intel's 10th generation Comet Lake CPUs. The new device will soon be available in the US, Canada, and European markets. It is good news for both developers and Linux enthusiast who wants Linux laptop with preloaded Ubuntu operating systems. Let us see new Linux XPS 13 developer edition specs and other information.

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BASH Fix Display and Console Garbage and Gibberish on a Linux / Unix / macOS

This article describes how to really clear the terminal screen or reset terminal in Linux or Unix-like system. In other words, you will learn how to clear console garbage and gibberish without exiting the session on your Linux/Unix/macOS/BSD systems.

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How to install htop on RHEL 8 using yum

I am a new user of Red Hat Enterprise Linux 8. How do I install htop on RHEL 8 using the yum command?

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Explain: {,} in cp or mv Bash Shell Commands

I often see commands as follows posted on blog or forums
cp /etc/httpd/httpd.{,.bakup}
OR
mv resume{z,}.doc
What is the purpose of {,} in Linux and Unix shell commands?

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FreeBSD Display Information About The System Hardware

FreeBSD comes with different utilities, which can be used to gather the information as per your needs.Let us see all commands that can display hardware information on the FreeBSD server or desktop.

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How to use yum-cron to automatically update RHEL/CentOS Linux

The yum command line tool is used to install and update software packages under RHEL / CentOS Linux server. I know how to apply updates using yum update command line, but I would like to use cron to update packages where appropriate manually. How do I configure yum to install software patches/updates automatically with cron job?

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Ubuntu Linux Add a User To Group www-data ( Apache Group )

How do I add a user to the Apache group called www-data under Ubuntu or Debian Linux server operating systems using the command line option?

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How To Install EPEL Repo on an RHEL 8.x

How do I install the extra repositories such as Fedora EPEL repo on an Red Hat Enterprise Linux server version 8.x?

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How to Install and Configure latest version of Ansible on Ubuntu Linux

I am a new Ubuntu Linux user. How do I install Ansible on a Ubuntu Linux 16.04/18.04 LTS or 17.10/18.10 desktop control machine?

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How to Find if Linux is Running on 32-bit or 64-bit CPU

{Updated} I am a new Linux system user. How do I determine if my CPU is 64bit or not on a Linux operating systems using command line option? How can I check Linux kernel is in 32 bit or 64 bit mode?

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How to add bash auto completion in RHEL 8 (Red Hat Linux)

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

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List or Check Installed Linux Kernels using command line

How do I list all installed kernel on Linux operating system? How do I find out current kernel version?

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How to install networked HP printer and scanner on Ubuntu Linux

I have HP Officejet Pro printer and scanner. How do I install HP Officejet Pro network printers and scanners on Ubuntu Linux? How can I install HP printer on Ubuntu Linux?

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How to check if port is in use on Linux or Unix

{Updated} For security reasons, it would be best to verify which TCP or UDP ports are listening on the Linux, FreeBSD or Unix server's network interfaces. This quick guide explains how to use the CLI utilities and code written in Bash, Perl, and Python to check for ports in USE or OPEN state.
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How to exclude file when using scp command recursively

{Updated} How do I tell scp command to exclude particular file or directory at the Linux/Unix command line?

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How To Set up SSH Keys on a Linux / Unix System

I recently read that SSH keys provide a secure way of logging into a Linux and Unix-based server. How do I set up SSH keys on a Linux or Unix based systems? In SSH for Linux/Unix, how do I set up public key authentication?

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How to check CPU temperature on Ubuntu Linux

How do I check CPU temperature in Ubuntu Linux using a command line and GUI tools on my Thinkpad laptop or Desktop computer?

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RHEL / Centos 6 - Install Nginx Using Yum Command

How can I install the latest version of Nginx web server On CentOS Linux 6 or Red Hat Enterprise Linux 6 using the yum command?

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10 Alpine Linux apk Command Examples

I am new Alpine Linux system admin user. How do I use apk command line utility for the package management on Apline Linux server running in cloud or a Linux container? How can I use the apk command for the package management?

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How to install htop on Ubuntu Linux using apt

I like htop output, but it is not installed by default on my Ubuntu cloud server. How do I install htop on Ubuntu Linux 18.04 LTS server?

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Linux / Unix whereis Command Examples

I am a new Linux and Unix-like system command line user. How do I find and locate the binary, source, and manual page files for a given command?

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How to install Ansible on Ubuntu 18.04 for IT automation

How do I install Ansible on Ubuntu 18.04 workstation? How can I set up and test Ansible playbooks using my Ubuntu Linux desktop?

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How to install curl command on Ubuntu Linux

I am trying to run the curl command from a shell script but getting the following error: bash: curl: command not found. How do I fix this on an Ubuntu Linux?

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Linux Monitor Hard Disks Temperature With hddtemp

There is an excellent little utility to monitor hard drive temperature. Most modern computer hard disk including SSD comes with S.M.A.R.T (Self-Monitoring, Analysis, and Reporting Technology). It is a monitoring system for computer hard disks to detect and report on various indicators of reliability, in the hope of anticipating failures.

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How to check disk space on Unix servers

I recently switched from a Windows server 2016 to a FreeBSD Unix server. I need to check disk space on Unix command line. How do I find out disk space utilization information using the Unix command-line option?

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How to install snapd on Fedora Linux system using dnf command

How do I install snapd on Fedora Linux to run and manage snaps?

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How to update source tree at /usr/src using svn on FreeBSD

I compiled custom FreeBSD kernel for my FreeBSD jail to use vnet. How do I update my FreeBSD /usr/src/ code tree? How can I update source tree at /usr/src on FreeBSD using svn command to patch and compile kernel again?

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Can I delete /var/cache/apt/archives for Ubuntu/Debian Linux?

I noticed that /var/cache/apt/archives/ taking lots of disk space on my AWS EC2 cloud server powered by Debian Linux. Can I delete /var/cache/apt/archives/ folder? Is it safe to remove all files? Do we absolutely necessary to keep all these files?

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