1 Readings, Assignments, Labs, and ToDoIndex

• Read (at least) these things (All The Words):
  • Week 14 Notes HTML – this file – Read All The Words
  • Data Mining
  • List of Commands You Should Know
  • Video Tutorials on Lynda.com
• Using your lynda.com account, watch Unix for Mac OS X Users

2 From the Class Notes link on the Course Home PageIndex

• Course Home Page
• Previous Week
• All Weeks

• Review last week. Did you do everything assigned last week?

3 From the Classroom Whiteboard/ChalkboardIndex

• Take notes in class! Your in-class notes would go here.

• I’ve extended all due dates to term end: April 17.

• Heartbleed bug explained https://xkcd.com/1354/
  • The programmer who made the SSL coding error at the start of 2012.
  • The code with the bug
  • How to update CentOS 6.5

• The useful diff command.

• The last command.

• In-class symlink exercise on the CLS:

  Create one of these symbolic link targets in /tmp
  Use your CLS userid as the link name in /tmp
  You may have to remove an existing name first
  
  Easy target:     linux
  Medium target:   symbolic link
  Hard target:     $$$ It's a "symbolic link" $$$

  You can check your work by executing the script /tmp/do.sh

• Data mining: Looking for lines that contain more than one text string:
  • $ fgrep 'string one' filenames... | fgrep 'string two'
  • can be extended to any number of text strings with more fgrep:
  • $ fgrep 'one' filenames... | fgrep 'two' | fgrep 'three' | fgrep 'four'
• Given a sector size of 512 bytes, approximately how many MegaBytes are unused before the start of a partition that begins on sector 4096?
  • Unused space is 512 bytes times 4096 sectors, divided by a MegaByte to get the answer in MegaBytes.
  • Computer Math: 1 K is 1024
  • Computer Math: 1 M is 1024 * 1024 or K * K
  • Computer Math: 512 is 0.5 * 1024 or 0.5 * K
  • Computer Math: 4096 is 4 * 1024 or 4 * K
  • Unused space is therefore 0.5 K bytes times 4 K sectors divided by K * K MegaBytes
    • = 0.5 K * 4 K / (K * K) MegaBytes
    • = 0.5 * 4 * (K * K) / (K * K) MegaBytes
    • = 0.5 * 4 * 1 MegaBytes
    • = 2 MegaBytes

4 Real Sysadmin WorkIndex

• Optional: Running commands on remote servers

• Selling the Web at CERN: An exchange between Aaron Swartz and Tim Berners-Lee.

• Constraints on the flow of ideas: Patents as Private Monopoly Taxation

• Epic Rap Battle: Steve Jobs vs Bill Gates

4.2 A Study in StudyingIndex

From the Class of Winter 2014:

Hi professor Ian. I hope you are doing fine. Today after our NOS exam, a few of us were going to the E building to study for the linux exam and we saw that the local church was giving away free breakfast. We stopped and we decided to have Allen’s juice to study for linux. We were able to get work done and we wanted to share this with you. Proof is attached in the picture. Thank you for your time:

Study Linux with Allen

Author: 
| 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/