CentOS System Administration Essentials电子书

CentOS System Administration Essentials

Table of Contents

CentOS System Administration Essentials

Credits

About the Author

About the Reviewers

www.PacktPub.com

Support files, eBooks, discount offers, and more

Why subscribe?

Free access for Packt account holders

Preface

What this book covers

What you need for this book

Who this book is for

Conventions

Reader feedback

Customer support

Downloading the color images of this book

Errata

Piracy

Questions

1. Taming vi

CLI trickery – shortcuts that you will love

Vim and vi

Getting the .vimrc setup the way you like

Search and replace

Learning to remove extraneous comments from a file with a few deft key strokes

Summary

2. Cold Starts

The GRUB and MBR

When is the root filesystem not the root filesystem?

Editing stanzas in GRUB

Adding a root entry to a stanza

Adding a kernel entry to a stanza

Adding an initrd entry to a stanza

Working on the GRUB console

Protecting the GRUB menu with passwords

Boot splashing with plymouth

Applying different themes

Summary

3. CentOS Filesystems – A Deeper Look

A magician's secret

Hard links

Symbolic links

Special permissions

The SUID bit

The SGID bit

The sticky bit

Naming your pipes

Understanding the command stat

The last access time

The last modified time

The last changed time

Enterprise filesystem shootout

What BTRFS has to offer

Installing BTRFS

Creating a BTRFS filesystem

Expanding a BTRFS filesystem

Volume management with BTRFS

Balancing the filesystem

Adding an entry to /etc/fstab

Creating an RAID1 mirror

Using BTRFS snapshots

Summary

4. YUM – Software Never Looked So Good

Managing software installation with RPM files

Creating your own RPM file

Creating the Plymouth theme

tup.plymouth

tup.script

Creating the theme RPM

Using YUM

YUM plugins

Creating a YUM Repository

/etc/yum.repos.d/

Summary

5. Herding Cats – Taking Control of Processes

Managing services with Upstart

Creating your own Upstart script

Managing processes

Using the pgrep command

Using the pstree command

Using the pkill command

Using the pmap command

Summary

6. Users – Do We Really Want Them?

Managing public and private groups

Linux groups

Adding users to groups

Evaluating private group usage

Getent

Quotas

Setting quotas

Scripting user creation

Summary

7. LDAP – A Better Type of User

LDAP concepts

Installing 389-ds

Configuring DNS or hostname records

Setting TCP keepalives

Setting file descriptors

Creating the directory server user and group

The EPEL repository

Installing and configuring 389-ds

Testing the installation

LDAP user account management

Adding users using the GUI console

Adding users from the command line

LDAP authentication

Summary

8. Nginx – Deploying a Performance-centric Web Server

Installing and configuring Nginx

Installing Nginx

Configuring Nginx

Configuring a 404 Document Not Found Error page

Installing PHP

Installing MySQL

Create dynamic web content

Summary

9. Puppet – Now You Are the Puppet Master

Installing the Puppet master

Configuring the firewall

DNS

Network Time Protocol

The Puppet lab repository

Puppet resource

Managing packages, services, and files

Classes

Resource definition

Puppet facts

Using include

Creating and testing manifests

Enrolling remote puppet agents

Summary

10. Security Central

Understanding PAM configuration files

Type

Control

The module path

Module arguments

Limits of PAM

Domain

Type

Item

SELinux

Reading the current SELinux mode

Setting the SELinux mode

Preventing mode changes from the command line

Understanding SELinux contexts

Troubleshooting SELinux

Hardening Linux

Password auditing

Preparing a password file

Cracking passwords

Weakening the algorithm

Hardening the password

Summary

11. Graduation Day

Securing remote access to your system

The SSH public key

Analyzing the risks of default settings

Populating the keystore

Public key authentication

Root logins

Conclusion

Best practices of OpenLDAP

Best practices of Nginx

Mastering Puppet

What's new in CentOS 7

Locale

Time and date information

Managing services

Additional ways to repair your machine than just using the single user mode

Remote management

Systemd and nonstandard subcommands

The Samba 4.1 package

Filesystem changes

Password policies

Summary

Index