Getting started on the command line

As a SysAdmin, the Linux command line is typically my happy place. The command line interface, the CLI, is the closest I can get to the raw power of my computers. It gives me access to tools that make my work easy, fast, and even fun. I use the command line so much that I sometimes forget how much power I have to manage my computers.

I also forget that it took me a long time to really understand the terminology that applies to the various tools that I use to access that command line. This article is about those tools and the sometimes confusing terminology necessary to function on the CLI.

How to use the basename command

The basename command is a GNU core utility for UNIX and UNIX-like systems, and is designed to remove the file suffix and leading directories from a filename. It’s a reasonable alternative to at least some uses of the cut command. You’re not likely to use it alone, but it’s an interesting tool to have available to you when constructing a complex command.

The Linux Philosophy for SysAdmins, Tenet 01 — Data Streams, the universal interface

Everything in Linux revolves around streams of data – particularly text streams.

I recently Googled “data stream” and most of the top hits are concerned with processing huge amounts of streaming data in single entities such as streaming video and audio, or financial institutions processing streams consisting of huge numbers of individual transactions. This is not what we are talking about here although the concept is the same and a case could be made that current applications use the stream processing functions of Linux as the model for processing many types of data.

How to do fast, repeatable Linux installations #3 — Ansible

In previous articles about my use of automation in performing post-install tasks for new Linux installations, Those approaches worked well for the times I used them, but as the requirements of my network and the hosts connected to it grew and became more complex, the capabilities of those tools couldn’t keep up.

I needed a new method for doing post-install tasks. I also needed new ways to perform other tasks, too. I started working with Ansible to first familiarize myself with it and then to perform more complex tasks such as Fedora updates and my post-install tasks.

How to create and use Public/Private/KeyPairs with SSH

SSH is an important mechanism for secure connections between Linux hosts. SSH is a software-based virtual private network (VPN) tool that can create a secure connection whenever needed. It can be used to securely login to any remote host so long as you have proper credentials, and it can be used to enhance tools such as tar and other backup programs like rsync so that remote hosts can be easily backed up to a local system. The scp (secure copy) program uses the SSH encrypted tunnel to copy files between a local host and a remote one.