Linux System Administration in 3 Weeks (2024)

Linux system administrators are in the trenches keeping systems healthy so that users and customers enjoy a positive computing experience. And the Linux command line is where the system administration action is.

Join fellow sysadmin Ken Hess to get acquainted with Linux and system administration. You’ll begin with the shell, the filesystem layout, and system navigation, then dive deeper into managing users and system security. You’ll also examine user maintenance, permissions, security, working with devices, and general commands for navigating the filesystem—and pick up a few housekeeping tips along the way.

Week 1: Introduction to the Linux Command Line

In Week 1, you’ll find out where everything is and what it does. You’ll examine the Linux shell and the Linux filesystem hierarchy, make command comparisons to Windows systems, and learn how to navigate the filesystem, list processes, and check system health.

Week 2: User Accounts and User Account Management

In Week 2 you’ll go deeper into Linux to learn the differences between the root user account, service accounts, and user accounts, and you’ll get a lesson on the su and the sudo commands plus an introduction to users and groups. You’ll also learn how to create and modify user accounts, how to protect the root user account, and how to set up service accounts.

Week 3: Learning Linux Permissions and Security

In the final week, you’ll encounter basic Linux file and directory permissions and figure out how to set and modify them. And you’ll learn how to protect the SSH daemon.

NOTE: With today’s registration, you’ll be signed up for all three sessions. Although you can attend any of the sessions individually, we recommend participating in all three weeks.

By the end of this live, hands-on three-part series, you’ll understand:

Week 1: Introduction to the Linux Command Line

• The Linux Bash shell, where you are on the system, and how to interact with the shell through commands
• The Linux filesystem, including important directories with some comparisons to the Windows filesystem
• The Linux process table, the top command, and its indication of system health

Week 2: User Accounts and User Account Management

• User accounts and general privileges
• The root user account and its all-powerful position
• When to use su and sudo, and the pitfalls of the root user account
• How to create, modify, and remove user accounts
• How to protect the root user account
• What service accounts are and how to create them

Week 3: Learning Linux Permissions and Security

• Basic system security
• File and directory permissions and how to set them
• Numerical and literal permissions settings
• The umask and what it does
• How to protect the SSH daemon

And you’ll be able to:

Week 1: Introduction to the Linux Command Line

• Navigate the Linux filesystem
• Find command locations
• Use man pages
• Use the top command
• Perform some basic troubleshooting

Week 2: User Accounts and User Account Management

• Explain the differences between the root, user, and service accounts
• Create, modify, and remove user accounts
• Use su and sudo
• Protect the root user account
• Create a service account

Week 3: Learning Linux Permissions and Security

• Explain basic Linux system security
• Explain file security through permissions
• Set and modify file permissions
• Explain the umask
• Protect the SSH daemon

• You’re an entry-level or junior system administrator who wants to learn more.
• You work with Windows but need to learn Linux.
• You want to become a Linux system administrator.

• Some experience with the Windows or *nix command line or comfort in a nongraphical environment

Recommended preparation

• Read The Linux Command Line, second edition (book)

Recommended follow-up

• Take Linux Under the Hood (live online training course with Sander van Vugt)
• Take Linux Fundamentals Bootcamp (live online training course with Sander van Vugt)

Week 1: Introduction to the Linux Command Line

Overview of Linux (15 minutes)

• Presentation: Why Linux?; What does a Linux system administrator do?; job opportunities in Linux system administration
• Group discussion: Why are you interested in Linux system administration?

Log in and look around (45 minutes)

• Presentation: Logging in and out of a Linux system; some basic starting commands; similarities and differences to Windows
• Hands-on exercises: Learn basic navigation; get to and from places on the filesystem
• Q&A
• Break

Searching the filesystem (30 minutes)

• Presentation: Finding commands and files on Linux; using search commands
• Hands-on exercise: Search for commands and files

Getting help with commands (30 minutes)

• Presentation: How to use the online help system
• Hands-on exercise: Use man pages to find a command’s options
• Q&A
• Break

Introduction to processes (30 minutes)

• Presentation: The process table; using the top command to view processes
• Hands-on exercises: Use the top command to get a process list; change top’s view

Basic troubleshooting (30 minutes)

• Presentation: Checking available space; checking memory; using top; killing and restarting processes; removing files; kicking a user off the system; rebooting
• Hands-on exercise: Kill a process
• Q&A

Week 2: User Accounts and User Account Management

User accounts overview (15 minutes)

• Presentation: The root, user, and service accounts
• Group discussion: What’s the purpose of each account type?

Using su, sudo, and the root account (45 minutes)

• Presentation: Multiple ways to become root; the sudo and visudo commands and the /etc/sudoers file; su command options for becoming root; log in as root
• Hands-on exercise: Become the root user in two different ways and explain how each works
• Q&A
• Break

Creating, modifying, and removing user and group accounts (60 minutes)

• Presentation: User and group accounts demystified; default user and group accounts; creating a group account with grpadd and useradd; removing a user account with userdel; modifying a user account with chuser
• Group discussion: Why is user and group account management so important?
• Hands-on exercise: Become the root user in two different ways and explain how each works
• Q&A
• Break

Protecting the root user account (30 minutes)

• Presentation: The root account password; renaming root; the root directory
• Group discussion: Why must you protect the root account?

Creating service accounts (30 minutes)

• Presentation: Service accounts as security holes; ways to protect service accounts; what service accounts do
• Hands-on exercise: Create a service account as a noninteractive account
• Q&A

Week 3: Learning Linux Permissions and Security

Introduction to Linux system security (15 minutes)

• Presentation: The myth of security; the importance of backups and snapshots
• Group discussion: Why is security a myth?
• Q&A
• Break

File and directory security: Permissions (45 minutes)

• Presentation: Read, write, and execute (rwx); numerical values; permissions on files and directories
• Group discussion: What’s the importance of carefully setting file and directory permissions?
• Hands-on exercise: Change file permissions
• Q&A
• Break

Managing user security through groups and others (10 minutes)

• Presentation: Introduction to Linux groups
• Group discussion: Why is managing groups better than managing individual security for users?
• Q&A

Group permissions (20 minutes)

• Presentation: Manage access for groups -g-
• Group discussion: What must you be careful of when managing group permissions?
• Hands-on exercise: Grant group access to files and directories
• Q&A

Other or world permissions (30 minutes)

• Presentation: Manage access for groups --o
• Group discussion: Why must you be especially sensitive about world permissions?
• Hands-on exercise: Restrict access to files and folders.
• Q&A
• Break

The umask concept (15 minutes)

• Presentation: What unmask means to the user
• Group discussion: What’s the importance of the umask setting?
• Q&A

Protecting the SSH daemon: Permissions (45 minutes)

• Presentation: What’s a daemon?; the SSH daemon; SSH and SSHD configuration files
• Group discussion: Why bother protecting SSHD if the communications are encrypted?
• Hands-on exercise: Deny root access over the network to SSH logins
• Q&A