1 TAC2000/ IP Telephony Lab Advanced Linux Administration Language: Offered in English Instructor: Dr. Quincy Wu ( ) Time: Tuesday 17:30-20:00 Place: Computer Center 027

2 TAC2000/ IP Telephony Lab Reading Requirement  Textbook Nate Campi and Kirk Bauer, "Automating Linux and UNIX System Administration", 2nd Ed. Publication: Berkeley, Calif., New York Springer Science & Business Media, (NCNU NetLibrary) Nate Campi and Kirk Bauer, "Automating Linux and UNIX System Administration", 2nd Ed. Publication: Berkeley, Calif., New York Springer Science & Business Media, (NCNU NetLibrary)  References Online manpage Online manpage GNU Info GNU Info Linux Documentation Project ( Linux Documentation Project ( LAMP: The Open Source Web Platform ( LAMP: The Open Source Web Platform ( Librenix - Linux Sysadmin Portal ( Librenix - Linux Sysadmin Portal ( Linux Magazine ( Linux Magazine ( Linux Journal ( Linux Journal (

3 TAC2000/ IP Telephony Lab Three Hours in Each Week  Chapter presentation (60min)  Package introduction (45min*2)  Hands-on and free Q&A  In addition to the 3 hours in class, you also need to spend 3 hours in reading the textbook 3 hours in reading the textbook 3 hours to try installing and configuring new services 3 hours to try installing and configuring new services 3 hours to read on-line documents 3 hours to read on-line documents

4 TAC2000/ IP Telephony Lab Evaluation  Homework (30%)  Oral Presentation (30%)  Participation (20%)  Term Project (20%)  Active participation is expected. Everyone must ask/answer questions during a presentation.

5 TAC2000/ IP Telephony Lab Outline  Introducing the Basics of Automation  Basic Tools  Using SSH to Automate System Administration Securely  Configuring Systems with cfengine  Creating Login Scripts and Shell Scripts  Pre-Installation: Network Preparation and Management  Automating and Customizing Installation  Automatic System Configuration  Sharing Data Between Systems  Packages and Patches  System Maintenance and Changes  Generating Reports and Analyzing Logs  System Monitoring  Improving System Security  Backing Up and Restoring Data  User Interfaces

6 TAC2000/ IP Telephony Lab Any Question So Far?

7 TAC2000/ IP Telephony Lab Importance of Automation  You can configure everything by hand, if you only manage 2 or 3 computers.  As the number of systems grows to more than ten, you need to spend time repeating the same things over and over again.  During the so- called “tech downturn” around the year 2003 in Silicon Valley, you may suddenly find yourself the sole member of what had been a three- person system- administration team. The number of systems and responsibilities were increasing, while staffing levels had dramatically decreased. The number of systems and responsibilities were increasing, while staffing levels had dramatically decreased.

8 TAC2000/ IP Telephony Lab Tools in This Book  The Bash shell  Perl  Cfengine  Regular expressions  The grep command  The sed stream editor  AWK

9 TAC2000/ IP Telephony Lab Do You Need Automation?  If you have only one system sitting on your desk at home, you can do everything manually. Many people do. Many people do.  But, consider routine tasks such as Performing backups Performing backups Apply security updates Apply security updates Uninstall a package Uninstall a package  If you have used RPM (RedHat Package Manager), you know how useful it is. Log file rotation Log file rotation  See an example under /var/log  The “logrotate” utility on Linux Database update Database update  Run “updatedb” command periodically to generate most up-to-date “/var/lib/mlocate/mlocate.db” to be search by the command “locate”.  All these tasks and more can happen quietly and automatically from within a standard UNIX or Linux system.

10 TAC2000/ IP Telephony Lab Do You Need Automation? (cont.)  Automation is already a core part of UNIX philosophy, and cron jobs have historically been the de facto method for automating UNIX tasks. If a disk fills, set up a log- rotation script run from cron that deletes unneeded temporary files—whatever addresses the root cause. If a disk fills, set up a log- rotation script run from cron that deletes unneeded temporary files—whatever addresses the root cause. If a process dies, set up a process monitor to restart it when it exits. If a process dies, set up a process monitor to restart it when it exits.  In later chapters, we will show you how to accomplish these tasks.

11 TAC2000/ IP Telephony Lab What Will You Gain?  Saving Time  Reducing Errors  Documenting System Configuration Policies

12 TAC2000/ IP Telephony Lab What Do System Administrators Do?  Tedious, repetitive tasks (a.k.a. boring tasks)  New, innovative tasks (a.k.a. why you love the job)  Answering users’ questions, or otherwise dealing with monitoring alarms, issues or emergencies (a.k.a. pulling your hair out)  The goal of this class is to help you create new and innovative solutions to eliminate those tedious and repetitive tasks.  Moreover, you will learn how to create a system that detects and fixes many problems before they come to the attention of the users.

13 TAC2000/ IP Telephony Lab Homework #1  Use VirtualBox to create a virtual machine on your desktop. If you have limited memory on your desktop PC, you may want to request a lower amount of memory (e.g. 256MB) for the virtual machine. If you have limited memory on your desktop PC, you may want to request a lower amount of memory (e.g. 256MB) for the virtual machine.  Install CentOS 5.4 on it. Choose “Red Hat” as the OS type. Don’t choose 64-bit type. Choose “Red Hat” as the OS type. Don’t choose 64-bit type.  Read some documents to know the difference between “find” and “locate”.