System Administration Computer Center CS NCTU 2 What

System Administration

Computer Center, CS, NCTU 2 What System Administrator Should do? (1) q Ordinary list • • • Install new system, programs and OS updates Monitoring system and trying to Tune performance Adding and removing users Adding and removing hardware Backup and Restore Security

Computer Center, CS, NCTU 3 What System Administrator Should do? (2) q Non-technique list • • • Helping users Maintaining documentation Moving furniture Burning your liver Good communication and memorization

Computer Center, CS, NCTU What System Administrator Should do? (3) q The best words to describe the job • Thankless job. Ø http: //www. sysadminday. com/ • System administration is like keeping the trains on time; no one notices except when they’re late. • 氣象局：「我們對的時候，沒人記得；我們錯的時候，沒人忘 記。」 q Philosophy of system administration • • • 4 Know how things really work. Plan it before you do it. Make it reversible Make changes incrementally. Test before you unleash it.

Computer Center, CS, NCTU 5 What System Administrator Should do? (4) q Flow of Change

Computer Center, CS, NCTU What you can learn in this course? q Mostly, the skill to be a candidate of system administrator q Secondary, information about CS computer center q System Admin / Network Admin ? • Play with computers q What Free. BSD can do. q 資安學程 http: //isc. cs. nctu. edu. tw/ 6

Computer Center, CS, NCTU 7 Attitude q Attend every class q Do every exercise • As early as possible • On your own q Read book and practice at least 6 hours every week • Recommend: more than 1. 5 hours/day averagely. q Collect information on the internet

Computer Center, CS, NCTU Syllabus q Website: • http: //www. cs. nctu. edu. tw/~liuyh/course/sysadm/ q Instructors: • 劉用翔 liuyh@cs. nctu. edu. tw • 蔡佳宏 chiahung@cs. nctu. edu. tw • 翁綜禧 chwong@cs. nctu. edu. tw q Time: • Tue. IJK (PM 6: 30 ~ 9: 20) q Place: • EC 115 q TAs: • We might get about 3~4 TAs. • Email to TAs: (TBA) q Textbook: • UNIX System Administration Handbook, " 3 rd ed. 8

Computer Center, CS, NCTU 9 Syllabus – Content q We will cover the following chapters in this semester (Sys. Adm): • Chapter 1 ~ 12 • Chapter 13, 17, 18, 23, 26 • Shell Programming q The following chapters is covered in the next semester (Net. Adm): • • Chapter 14, 15, 16, 19, 20 , 22 News Server SNMP Perl Programming

Computer Center, CS, NCTU 10 Syllabus – Text book outline q. Chap 1 – Where to start. q. Chap 14 – Routing q. Chap 2 – Booting and shutting down q. Chap 15 – Network hardware q. Chap 3 – Rootly powers q. Chap 16 – The domain name system q. Chap 4 – Controlling processes q. Chap 17 – The network file system q. Chap 5 – The Filesystem q. Chap 18 – Sharing system files q. Chap 6 – Adding new users q. Chap 19 – Electronic mail q. Chap 7 – Serial device q. Chap 20 – Network management and debugging q. Chap 8 – Adding a disk q. Chap 21 – security q. Chap 9 – Periodic process q. Chap 22 – Web hosting and internet servers q. Chap 10 – Backups q. Chap 23 – Printing q. Chap 11 – Syslog and log files q. Chap 24 – Maintenance and environment q. Chap 12 – Drivers and the kernel q. Chap 25 – Performance analysis q. Chap 13 – TCP/IP Networking q. Chap 26 – Cooperating with Windows.

Computer Center, CS, NCTU 11 Syllabus – Grade Policy q Mid • 15 ~ 20% q Final • 15 ~ 20% q Exercise (Homeworks) • 60 ~ 70% Ø No Delay Work Ø 4 exercises Ø 1 term project

Computer Center, CS, NCTU What you should prepare? q Background knowledge • Basic of TCP/IP Networking (not required) q Environment • One dedicated PC Ø Or two OS in your PC. • One extra IP q Yourself • Your hard study 12

Computer Center, CS, NCTU 13 Finally, Am I OK to take this course? q Are you willing to devote yourself to exercise? • Yes! Please come q Are you newbie in this area? • Yes!? It’s ok, Please come q Do you take more than 3 major courses? • Yes!? ? ? It is quite dangerous, but I can not stop u

Basic knowledge in this course

Computer Center, CS, NCTU 15 Login q SSH (Secure Shell) • Pu. TTY: http: //www. chiark. greenend. org. uk/~sgtatham/putty/download. html • Chinese Environment: http: //www. cs. nctu. edu. tw/help/putty. html

Computer Center, CS, NCTU 16 Commands q Useful commands • • • • passwd, chsh, chfn, chpass ls ps, top mkdir/rmdir cp/mv/rm write Email reader: mutt, …etc. News reader: tin Connecting: ssh/telnet Manual: man, info, …etc. Editor: vim, joe, ee, …etc. File Transmittion: ftp, ncftp, lftp, scp, wget, curl, …etc. Compilers: gcc, g++, javac, …etc. Scripting: perl, php, ruby, python …etc. login/exit/logout/screen

Computer Center, CS, NCTU Conventions q Syntax of commands: • • Anything between “[” & “]” – are optional. Anything followed by “…” – can be repeated. {a | b} – you should choose one of them. Example: Ø bork [-x] { on | off } filename … bork on /etc/hosts bork –x off /etc/hosts /etc/passwd bork –x /etc/hosts bork -h /etc/hosts q Globing characters • • 17 “*” matches zero or more characters. “? ” match one character. “~” (twiddle) means home directory “~user” means home directory of user ○ ○ Ｘ Ｘ

Computer Center, CS, NCTU man pages (manual) q man pages (manual) • Contain descriptions of Ø Individual command. – % man cp Ø File format. – % man rc. local Ø Library routines. – % man strcpy 18

Computer Center, CS, NCTU 19 man command q. Command • % man [section] title (BSD) Ø % man printf Ø % man 3 printf Ø % man –k exit (printf command) (C Standard printf func. ) (keyword search) q. Man pages organization AT&T BSD %man Contents 1 1 User-Level commands and applications 2 2 System calls and kernel error code 3 3 Library calls 4 5 Standard file format 5 7 Miscellaneous files and documents 6 6 Games and demonstrations 7 4 Device Drivers and network protocols 1 m 8 System administration commands 9 9 Obscure kernel specs and interfaces

Break time. Computer Center, CS, NCTU 20 Q&A