CentOS related tutorial/FAQ

How to determine number of CPUs on Linux using command line

last updated June 7, 2019 in CentOS, Debian / Ubuntu, Hardware, Linux, RedHat and Friends, Suse

I am a new Linux system admin. How do I obtain the number of CPUs and cores in the Linux system from the command line? How do I determine the number of CPUs on Linux?

Use oathtool Linux command line for 2 step verification (2FA)

last updated May 11, 2019 in CentOS, Debian / Ubuntu, Linux, RedHat and Friends, Security, Suse

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?

Linux bash exit status and how to set exit status in bash

last updated March 7, 2019 in BASH Shell, CentOS, Debian / Ubuntu, FreeBSD, Linux, Suse, UNIX

Can you explain bash exit status code? How do I set bash exit status in my Linux shell scripts?

How to find Intel NUC BIOS version and model on Linux

last updated January 26, 2019 in BASH Shell, CentOS, Debian / Ubuntu, Hardware, Linux, RedHat and Friends, Suse

I installed Linux on Intel NUC. I need to find Intel NUC BIOS version. How do I find out BIOS version, date, and model name of my Intel NUC using Linux command-line options?

Install Google Chrome 73 on CentOS 7 using yum command

last updated April 8, 2019 in CentOS, Linux, Package Management

I am a new CentOS Linux 7 desktop user. How do I install Google Chrome 72 on CentOS 7 Linux desktop?

How to override content type with Nginx web server

last updated January 21, 2019 in CentOS, Debian / Ubuntu, FreeBSD, Linux, Nginx, RedHat and Friends, Suse, UNIX

I configured Nginx server. However, it is sending the wrong content type. I need to force Nginx to send specific “Content-Type: text/xml; charset=UTF-8“. How do I configure Nginx to override content type for given URL location?

How to hide files and directories in Linux

last updated January 16, 2019 in BASH Shell, CentOS, Debian / Ubuntu, Linux, Suse

I am a new Linux user. How do I hide files and directories in Linux operating systems using the command line interface?

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