nixCraft Linux & Unix Sysadmin/DevOps Tutorial Newsletter

[nixCraft]

Welcome to nixCraft Linux/Unix newsletter for Thursday, 10 October 2019. I hope you will enjoy this version of the newsletter.

• 21 Examples To Make Sure Unix / Linux Configuration Files Are Free From Syntax Errors {trending}
  This post explains how to quickly find out a syntax error for popular servers and test configuration files for syntax errors running on Linux, Unix, and *BSD family of oses.
   
• How To Use tar Command Through Network Over SSH Session {trending}
  Did you know you can use the tar command over ssh sessions to transfer archives, files, backups and hard drive images securely? Pretty handy for Linux and Unix users, sysadmins and developers. See examples and usage.
   
• pfetch Linux and Unix hardware information tool
  The neofetch command like utility written in a bash shell. The main purpose of neofetch is to be used in screenshots to display other users what operating system or Linux distro you are using including theme, icons, hardware config and more. Now we have another tool called pfetch. It is a pretty system information tool written in POSIX sh. Let us see how to install and use pfetch Linux and Unix hardware information tool.
   
• How to find serial number of Lenovo (any other device) laptop from Linux {trending}
  I need to list serial number of Lenovo laptop to check warranty. How do I find a serial number of Lenovo laptop from Linux command line without rebooting and opening BIOS option? How do I find find serial number of Lenovo ThinkPad laptop from the Linux CLI?
   
• Ubuntu Linux Remove / Delete PPAs apt-get command
  Over time I have added way too many PPAs using the add-apt-repository command on Ubuntu Linux 16.04/18.04 LTS server for testing purpose. How can I delete or remove those PPAs? Is there a command to list all PPAs?
   
• How to open ssh port using ufw on Ubuntu/Debian Linux
  How do I allow incoming SSH connections from a specific IP address or subnet on a Ubuntu or Debian Linux server using ufw? How do I open ssh port using ufw on Ubuntu or Debian server?
   
• Configure Ubuntu Pi-hole for Cloudflare DNS over HTTPS {trending}
  Pi-hole is a free and open source software to block Internet ads and tracking domains. This page shows how to configure Cloudflare DNS over HTTPS service along with Pi-Hole server running on Ubuntu Linux 18.04 LTS.
   
• How to check Ansible version and install latest one on Linux/Unix
  How do I check Ansible version (IT automation tool) on my Linux or Unix-like server using the command prompt?
   
• Linux Find Out Last System Reboot Time and Date Command {trending}
  So, how do you find out your Linux or UNIX-like system was last rebooted? How do you display the system shutdown date and time?
   
• How to install htop on Amazon Linux AMI
  I am a new user of Amazon Linux AMI operating system. How do I install htop on Amazon Linux AMI using the yum command?
   
• Amazon Linux AMI install mysql client programs for RDS
  How do I install mysql command for management Amazon RDS or Managed Databases for Amazon Lightsail on Amazon Linux AMI?
   
• Ubuntu 18.04 remove all unused old kernels {trending}
  How do I remove all unused old kernels in Ubuntu Linux 18.04 LTS using the command line?
   
• Change default shell to bash on Macos Catalina {trending}
  I noticed that my default shell set to zsh on Macos Catalina. How do I change my default shell to bash on Macos Catalina using the command line or GUI options?
   
• Change netplan renderer from networkd to NetworkManager
  I prefer to use NetworkManager on my Ubuntu desktop, but currently, it is using networkd. As a result, I cannot set up or configure NetworkManager using GUI tools. Is there anyway to change netplan renderer from networkd to NetworkManager running on Ubuntu Linux? How can I change netplan renderer in Ubuntu Linux?
   
• Apache with Let’s Encrypt Certificates on CentOS 8 {trending}
  I read that Let’s Encrypt is a free, automated, and open certificate for web server and other usages. How do I secure Apache with Let’s Encrypt Certificates on CentOS 8?
   
• How to install whois on RHEL 8 / CentOS 8
  I deployed RHEL 8 in the cloud server. However, I am unable to find the whois command on my newly created RHEL 8 Linux server. It says ‘-bash: whois: command not found‘ I tried yum install whois, but it failed too. How do I install whois command on RHEL/CentOS 8 Linux using the command line?

Until next time.

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