Linux System Administration

1. Requirements for a Linux System Administrator . . . . . . . . . . . . . . . . . . . . . . . . 1
About This Book 2
How Can We Help? 2
Where Do You Start? 3
Do You Need a Book? 3
Who Needs You? 4
What System Managers Should Know About Linux 6
What’s Next 7
2. Setting Up a Linux Multifunction Server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Server Requirements 9
Installing Debian 10
Logging in Remotely 12
Configuring the Network 13
Changing the Default Debian Packages 15
Setting Up Quotas 16
Providing Domain Name Services 18
Adding a Relational Database: MySQL 20
Configuring Mail Securely with Postfix, POP3, and IMAP 22
Putting Apache to Work 33
Adding FTP Services with ProFTPD 34
Summarizing Your Web Statistics with Webalizer 35
Synchronizing the System Clock 36
Installing Perl Modules Needed by SpamAssassin 36
What’s Next 37

3. The Domain Name System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
DNS Basics 38
Getting into the BIND 40
Setting Up a DNS Server 41
Configuring an Authoritative DNS Server 44
Editing the Configuration Files 50
BIND Tools 62
Troubleshooting BIND 66
What’s Next 71
4. An Initial Internet-Ready Environment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
Installing ISPConfig 74
Setting Up a Server and Users with ISPConfig 83
Safeguarding a Linux Web Server 96
What’s Next 101
5. Mail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Key Mail Service Terms 103
Postfix, Sendmail, and Other MTAs 103
The Postfix SMTP Mail Server on Debian 105
Adding Authentication and Encryption 111
Configuring POP3 and IMAP Mail Delivery Agents 119
Email Client Configuration 120
What’s Next 121
6. Administering Apache . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Static and Dynamic Files 122
A Simple LAMP Setup 123
Installation 124
Apache Configuration Files 127
Logfiles 140
SSL/TLS Encryption 142
suEXEC Support 143
Benchmarking 144
Installing and Administering Drupal 145
Troubleshooting 149
Further Reading 153