2020-04-14 CANCELLED: Introduction to GNU/Linux and SSH (HILS1S20)

This course provides an introduction to GNU/Linux, the Unix shell and how to work on remote systems using Secure Shell (SSH). GNU/Linux is a family of open source operating systems, powering all different kinds of hardware: wearable and mobile devices, desktop and notebook computers, the majority of web servers and cloud instances as well as most high performance computing clusters and supercomputes. The typical command line interface is a Unix-like shell. It serves as interactive command and scripting language, allowing users to control the system and to automate tasks of varying complexity. SSH is a cryptographic network protocol which is typically used to login and execute commands on remote (GNU/Linux) systems.

The course opens with a short historical overview of GNU/Linux and some common concepts and terminology will be explained. Then the focus is directed toward working with the Unix shell on a remote system by guiding participants to install and configure a SSH client on their local systems. Different applications for remote access and file transfer will be introduced. Shell commands will then be used to navigate the file system and directories of a remote system, then the mechanisms of file manipulation and ownership will be explored. This is followed by the presentation of additional useful commands and concepts, as well as a discussion of the characteristics of the shell environment. A conceptual and practical introduction to SSH keys will also be given.

This material will be presented as a combination of lectures, demos and hands-on sessions, with a focus on the latter. There will be breaks during the session.

Participants will gain essential knowledge and skills necessary to successfully connect to and interact with the command line interface of remote GNU/Linux systems, a basic requirement when using the LRZ supercomputing and cloud infrastructure for their own projects.

Schedule (tentative):

• Introduction to LRZ as institute of the Bavarian Academy of Sciences and Humanities (B)
• Overview of GNU/Linux as operating system (components, distributions, free software, desktop environment, shell environment) (C)
• Setting up a UNIX-like shell (on different operating systems or a web-based emulated environment) (B)
• Basic SSH Client Usage (OpenSSH, PuTTY) (B)

15 min break

• File system hierarchy and navigation (pwd, ls, cd, tab-completion) (B)
• Command syntax (command + options/switches/flags + argument) (B)
• How to get help (-h, --help, man) (B)
• File manipulation (mkdir, touch, nano, cp, mv, rm, rmdir), shortcuts (., .., ~), absolute vs. relative paths (B)
• SCP/WinSCP/FileZilla (secure copy between hosts) (B)

15 min break

• File ownership and permissions (chmod) (I)
• Environment variables (env, echo, export) (B)
• SSH keys (partly for convenience) (I)

All participants are expected to bring their own laptops.