% CST8207 Week 08 Notes -- Quoting, File System, Inodes, Hard and Soft links, Disk Usage % Ian! D. Allen -- -- [www.idallen.com] % Winter 2015 - January to Apil 2015 - Updated 2015-10-26 04:27 EDT - [Course Home Page] - [Course Outline] - [All Weeks] - [Plain Text] Readings, Assignments, Labs, Tests, and ToDo ============================================ - Read (at least) these things (All The Words): 1. [Week 08 Notes HTML] -- this file -- **Read All The Words** 2. [Quoting] 3. [Unix/Linux File System - directories, inodes, etc.] 4. [Hard links and Unix/Linux file system index nodes (inodes)] 5. [Hard links and Unix file system nodes (inodes)] 6. [Unix/Linux Disk Usage, Hard Links, Finding Inodes] 7. [Symbolic Links] 8. [List of Commands You Should Know] 9. [Video Tutorials on Lynda.com] - Create your [lynda.com] account and watch [Unix for Mac OS X Users] - **3. Working with Files and Directories** - Naming files 5m 41s - use quotes to surround names with blanks or special characters - Hard links 5m 30s - Symbolic links 6m 36s - **5. Commands and Programs** - Disk information commands 6m 8s - df, du, Assignments this week --------------------- Check the due date for each assignment and put a reminder in your agenda, calendar, and digital assistant. - Read All The Words, Do, and then Submit via Blackboard: - Bonus (optional) [Assignment #04 HTML] -- the VIM text editor - Bonus (optional) [Assignment #06 HTML] -- Midterm #1 corrections - There is a checking program available to check your file format for this bonus assignment, but only people who Read All These Words will know about it. Wrong format means no marks. - [Assignment #07 HTML] -- start-up files, environment, search PATH, quoting, hard and soft links, disk usage - Really do **Read All The Words**. You don't get a second chance to get it right. Lab work this week ------------------ - Bonus (optional) [Assignment #04 HTML] about VIM has a new due date - Bonus (optional) [Assignment #06 HTML] about Midterm #1 is ready - There is a checking program available to check your file format for this bonus assignment, but only people who Read All These Words will know about it. - [Assignment #07 HTML] is ready (start-up files, environment, search PATH, quoting, hard and soft links, disk usage) - Work on the above assignments in your lab period; ask questions. Upcoming tests and quizzes -------------------------- Read the [Test Instructions] (all the words) before your next midterm test. 1. Second Midterm test: 45 minutes; in class 8am Thursday in Week 9 (March 12) - Midterm Tests take place in your 8am lecture hour, not in your lab period. - Quizzes will be posted based on the practice test. 2. Final Exam: 180 minutes; Tuesday April 21 11am to 2pm in room C144 - Take a bathroom break before you sit down for three hours! ### Midterm Test #2 - Midterm #2 takes place 8am Thursday March 12 (Week 9) in your scheduled lecture hour (not in your lab period). - For full marks, you must read the [Test Instructions] before the test for important directions on how to enter your answers, your lab (not lecture) section number, and the test version number on the question sheet and the mark-sense forms. - There may be more questions on the test than you can answer in the time allowed; answer the ones you know, first. - A set of practice questions and answers for the first midterm test is posted: [Practice Tests and Answers]. - Blackboard will have some quizzes taken randomly from the practice test. See below. ### Quizzes: Midterm #2 Quiz This Blackboard quiz is one of several quizzes in this course. Each midterm and final exam will have an associated Blackboard quiz. See the course outline for the mark weight of all course quizzes, midterm tests, and exams. The Blackboard quizzes are open-book, but the midterm tests and final exam are closed-book. This Blackboard quiz is based on the [Midterm #2 Practice Test] questions that are posted in the [Class Notes][All Weeks]. See the [Week 05 Notes HTML] for details on how the quiz is marked. From the Class Notes link on the Course Home Page ================================================= - [Course Home Page] - [All Weeks] - Review last week. Did you do everything assigned last week? From the Classroom Whiteboard/Chalkboard ======================================== - This week: - learn how the file system really works - Useful command: `hostname` - Needed for [Assignment #07 HTML] Real Sysadmin Work ================== - [The Evolution of a Sysadmin] Course Linux Server private address working ------------------------------------------- The CLS private address `cst8207-alg.idallen.ca` has been re-enabled by ITS. Linux skills in hot demand -------------------------- **Demand For Linux Skills Rising This Year** *This year is shaping up as a really good one for Linux, at least on the jobs front. According to a new report (PDF) from The Linux Foundation and Dice, nearly all surveyed hiring managers want to recruit Linux professionals within the next six months, with 44 percent of them indicating they're more likely to hire a candidate with Linux certification over one who does not. Forty-two percent of hiring managers say that experience in OpenStack and CloudStack will have a major impact on their hiring decisions, while 23 percent report security is a sought-after area of expertise and 19 percent are looking for Linux-skilled people with Software-Defined Networking skills. Ninety-seven percent of hiring managers report they will bring on Linux talent relative to other skills areas in the next six months.* Linux skills in hot demand -------------------------- | From: Andrew Patrick | Subject: anybody looking for a Linux SysAdmin job? | Date: Wed, 4 Mar 2015 20:52:10 -0500 | One of my colleagues is trying to find Senior and Intermediate Linux SysAdmins for government contract work. This is long-term work with an immediate start, and it requires a Secret clearance. | This is an ASAP opportunity that should be filled by tomorrow. | If you know anybody who may be suitable, let me know. | Cheers. | -- | Andrew Patrick, Ph.D. | Email: | Web: | Phone/Text: (613) 277-9211 | Skype: andrewspatrick Locked out of CLS due to capital letter in userid ------------------------------------------------- Your userid is all lower-case. There are no capital letters. Trying an incorrect userid will lock you out of the CLS: Feb 24 23:12:11 Accepted password for xxxxnnnn from 99.246.28.196 Mar 3 22:11:09 Invalid user Xxxxnnnn from 99.246.28.196 Mar 3 22:11:16 Failed password for invalid user Xxxxnnnn from 99.246.28.196 Mar 3 22:11:24 Failed password for invalid user Xxxxnnnn from 99.246.28.196 Mar 3 22:11:33 Failed password for invalid user Xxxxnnnn from 99.246.28.196 Mar 3 22:11:43 Failed password for invalid user Xxxxnnnn from 99.246.28.196 Mar 3 22:11:52 Failed password for invalid user Xxxxnnnn from 99.246.28.196 Mar 3 22:12:11 Failed password for invalid user Xxxxnnnn from 99.246.28.196 Mar 3 22:12:37 refused connect from cpef87b8c0998e9-cmbcc81013650f.cpe.net.cable.rogers.com (99.246.28.196) Attacks on the Course Linux Server ---------------------------------- - Count the attacks: `fgrep -c "refused connect" /var/log/auth.log` - Another way to count the lines (less efficient): `fgrep "refused connect" /var/log/auth.log | wc` - Only show the last 10 lines: `fgrep 'refused connect' /var/log/auth.log | tail` - See the current list of *evil* host IPs: `less /etc/hosts.evil` ----------------------------------------------------------------------------- ![Take Notes in Class] -- | Ian! D. Allen - idallen@idallen.ca - Ottawa, Ontario, Canada | Home Page: http://idallen.com/ Contact Improv: http://contactimprov.ca/ | College professor (Free/Libre GNU+Linux) at: http://teaching.idallen.com/ | Defend digital freedom: http://eff.org/ and have fun: http://fools.ca/ [Plain Text] - plain text version of this page in [Pandoc Markdown] format [www.idallen.com]: http://www.idallen.com/ [Course Home Page]: .. [Course Outline]: course_outline.pdf [All Weeks]: indexcgi.cgi [Plain Text]: week08notes.txt [Week 08 Notes HTML]: week08notes.html [Quoting]: 440_quotes.html [Unix/Linux File System - directories, inodes, etc.]: 450_file_system.html [Hard links and Unix/Linux file system index nodes (inodes)]: 455_links_and_inodes.html [Hard links and Unix file system nodes (inodes)]: 455_links_and_inodesA.html [Unix/Linux Disk Usage, Hard Links, Finding Inodes]: 457_disk_usage.html [Symbolic Links]: 460_symbolic_links.html [List of Commands You Should Know]: 900_unix_command_list.html [Video Tutorials on Lynda.com]: 910_lynda_index.html [lynda.com]: http://algonquincollege.com/onlineresources/mobileStudent/lynda.htm [Unix for Mac OS X Users]: http://www.lynda.com/Mac-OS-X-10-6-tutorials/Unix-for-Mac-OS-X-Users/78546-2.html [Assignment #04 HTML]: assignment04.html [Assignment #06 HTML]: assignment06.html [Assignment #07 HTML]: assignment07.html [Test Instructions]: 000_test_instructions.html [Practice Tests and Answers]: PRACTICE_TEST_README.html [Midterm #2 Practice Test]: practicetest2.pdf [Week 05 Notes HTML]: week05notes.html [The Evolution of a Sysadmin]: https://training.linuxfoundation.org/images/lftc_evolution_sysadmin.jpg [Take Notes in Class]: data/remember.jpg "Take Notes in Class" [Pandoc Markdown]: http://johnmacfarlane.net/pandoc/