1 Readings, Assignments, Labs, and ToDoIndex

• Read (at least) these things (All The Words):
  • Week 12 Notes HTML – this file – Read All The Words
  • Unix/Linux Partitions and File Systems - fdisk, mkfs, mount, swap
  • List of Commands You Should Know
  • Video Tutorials on Lynda.com
• Using your lynda.com account, watch Unix for Mac OS X Users
  • 4. Ownership and Permissions 34m 58s
    • The root user 1m 57s
    • sudo and sudoers 5m 20s

 ____  _                       ____           ____                          
|  _ \| | ___  __ _ ___  ___  |  _ \  ___    / ___|___  _   _ _ __ ___  ___ 
| |_) | |/ _ \/ _` / __|/ _ \ | | | |/ _ \  | |   / _ \| | | | '__/ __|/ _ \
|  __/| |  __/ (_| \__ \  __/ | |_| | (_) | | |__| (_) | |_| | |  \__ \  __/
|_|   |_|\___|\__,_|___/\___| |____/ \___/   \____\___/ \__,_|_|  |___/\___|
                                                                            
 _____            _             _   _             
| ____|_   ____ _| |_   _  __ _| |_(_) ___  _ __  
|  _| \ \ / / _` | | | | |/ _` | __| |/ _ \| '_ \ 
| |___ \ V / (_| | | |_| | (_| | |_| | (_) | | | |
|_____| \_/ \__,_|_|\__,_|\__,_|\__|_|\___/|_| |_|
                                                  

2 From the Class Notes link on the Course Home PageIndex

• Course Home Page
• Previous Week
• All Weeks
• Next Week

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

http://xkcd.com/1316/

3 From the Classroom Whiteboard/ChalkboardIndex

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

• Updated Network Diagnostics with information from Kevin. See if this fixes your SSH problems into your Linux machines.

• Survey survey (really!): http://algonquincollege.fluidsurveys.com/surveys/karimif/student-course-feedback-survey/

• eText survey: http://algonquincollege.fluidsurveys.com/surveys/karimif/etext-survey/
  • $1000 in gift certificates

• Dogbert on satisfaction surveys

• Pay attention to how permissions work with su, sudo and shell redirection! See the notes on redirection in Users and Groups – sudo
  • $ sudo touch foo >bar
  • $ su -c 'touch foo' >bar
  • $ sudo cp /etc/shadow foo
  • $ su -c 'cp /etc/shadow foo'
  • $ sudo cat /etc/shadow >bar
  • $ su -c 'cat /etc/shadow' >bar

• The userdel command does not delete HOME directories (unless you use the -r option). What does ls show for a file’s user and group if that user and group have been deleted from the system? See userdel in Users and Groups – userdel

  # useradd redshirt
  # id redshirt
  uid=508(redshirt) gid=509(redshirt) groups=509(redshirt)
  # ls -ld /home/redshirt
  drwx------ 2 redshirt redshirt 4096 Nov 20 02:38 /home/redshirt
  # userdel redshirt
  # id redshirt
  id: redshirt: No such user
  # ls -la /home/redshirt
  [... what does ls show now? ...]

• Reminder that Assignment #12 HTML contains at the start short descriptions of the command names you need to complete the assignment. This is in addition to having the names mentioned in the List of Commands You Should Know.

• Reminder on searching the course notes: Recall that in a previous Assignment 4 you were shown how to use fgrep on the CLS to search for a string in all the course notes? Please do it.

  $ fgrep -l 'whois' newnotes/*.txt
  newnotes/900_unix_command_list.txt
  newnotes/assignment11.txt
  newnotes/week02notes.txt
  newnotes/week03notes.txt
  newnotes/week04notes.txt

• 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

• Your selected editor for crontab -e is in ~/.selected_editor and can be changed with select-editor
  • Choose VIM. Your CentOS Linux install has no other editor.
• Use an SMS Gateway List to find the email address of your SMS enabled phone, and email a test message directly to your phone. (May be subject to length restrictions and incur an arbitrary delay.)
  • SMS Gateway List (from Christopher Mckee) http://www.wigwag.com/devblog/send-free-sms-texts-through-gateways/
  • SMS Gateway List (from Matthew Mercier) http://martinfitzpatrick.name/list-of-email-to-sms-gateways/
  • SMS Gateway List http://www.notepage.net/smtp.htm
  • “I found out that when using wind mobile you have to send a text message to 4000 to initialize your mailbox.” – Christopher Mckee

find dir ! -type l -perm /o+w -ls

4 Real Sysadmin WorkIndex

• The full documentation on basic commands (better than man pages): https://www.gnu.org/software/coreutils/manual/

• Google propels Linux to the top http://www.techrepublic.com/article/google-propels-linux-to-the-top/#ftag=RSS56d97e7

• How to fix any computer

• Joke (from a Linux student):

Subject: joke, clean Why didn’t the chicken cross the road? Because he did not have an absolute path and could’t find his way. HAHAHAHAHA!

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/