Book Image

Linux for System Administrators

By : Viorel Rudareanu, Daniil Baturin
Book Image

Linux for System Administrators

By: Viorel Rudareanu, Daniil Baturin

Overview of this book

Linux system administration is an essential aspect of maintaining and managing Linux servers within an organization. The role of a Linux system administrator is pivotal in ensuring the smooth functioning and security of these servers, making it a critical job function for any company that relies on Linux infrastructure. This book is a comprehensive guide designed to help you build a solid foundation in Linux system administration. It takes you from the fundamentals of Linux to more advanced topics, encompassing key areas such as Linux system installation, managing user accounts and filesystems, networking fundamentals, and Linux security techniques. Additionally, the book delves into the automation of applications and infrastructure using Chef, enabling you to streamline and optimize your operations. For both newcomers getting started with Linux and professionals looking to enhance their skills, this book is an invaluable hands-on guide with a structured approach and concise explanations that make it an effective resource for quickly acquiring and reinforcing Linux system administration skills. With the help of this Linux book, you’ll be able to navigate the world of Linux administration confidently to meet the demands of your role.
Table of Contents (21 chapters)
1
Part 1: Linux Basics
7
Part 2: Configuring and Modifying Linux Systems
13
Part 3: Linux as a Part of a Larger System

Network interfaces and addresses in Linux

Network interface is a generic term for physical and virtual network links that can carry addresses. The correspondence between physical network cards and network interfaces as the kernel sees them is not one-to-one. A network card with four ports is a single PCI device, but every one of its ports is seen as a separate link by the kernel.

There are also virtual links. Some virtual links are tied to physical network ports, but other types are fully independent. For example, MACVLAN links allow administrators to send traffic from certain IP addresses using a different MAC address. Since an Ethernet interface by definition cannot have multiple MAC addresses, Linux solves that problem by creating virtual interfaces on top of a physical Ethernet port and assigning different MAC and IP addresses to it. Multiplexing Ethernet traffic using 802.1Q VLAN or 802.3ad QinQ (nested VLAN) is also done by creating a virtual link that is bound to a specific...