Please feel free to add things to this page that you felt were important for you to learn from the class sessions. In addition if you see terms here that are still fuzzy to you please say so.
Aug 20
Installed Ubuntu on laptops.
Install notes:
- Select US English
- Keyboard layout detect: NO (choose from the list, its easier)
- Do not configure network at this time
- Be Patient!! Have a LOT of patience while blue screen is loaing
- When doing a laptop use: Guided: use entire disk (dont choose this on your home computer with another operating system you would like to keep)
- Be Patient!! Don't give up here an older machine will take quite a while to load
Terms you might have heard
- Bios
- Boot Sequence
- Power down (hold power button for 5 seconds)
Aug 27
Intalled Ubuntu on new machines: (question - did doing the second install help understanding? )
Saw how to load applications on Ubuntu three different ways
- Synaptic Package manager
- Add/Remove Programs
- Terminal window /Command line
Discussed briefly the different flavors of Linux
Different Linux versions vary in length of support and some additional functionality
- Ubuntu
- Red Hat
- Centos
- Fedora
Terms and Concepts
- Server -- a server is software running on a machine
- Virtual Hosting - remote login
- Terminal Server
- Thin client /Dumb Terminal
- Scripts to install -- more info/examples to follow (needed now?)
- WINE -- windows emulator
September 3
Thin client - computer that attaches to a server where the server provides the software to run. The thin client operating systems serves to login a person and allows space for a user to work while logged on. All files are saved back on the server when the user logs out.
Edubuntu- Runs off of an Ubuntu base with functionality added just for educators. Think of it as a basic car (Ubuntu) that then can have different packages on it, i. e., SX, LX, LE etc. Edubuntu would be Ubuntu ED -- designed with educators in mind.
Please add notes etc here.
September 10
LTSP Day
Downloaded LTSP (or tried to) and installed on a Ubuntu/Edubuntu machine.
LTSP - Linux server terminal project -- an additional program that allows a thin client to log into the server. As above, think of the computer with Ubuntu on it as a car. The LTSP would be like adding a trailer hitch to the car to allow a trailer (thin client) to attach itself to the car. The car does all the driving and supplies all the power and the trailer doesnt go without the car.
To Intall LTSP
- In this example the computer would need two network interface cards. One NIC talks to the Internet, and the other NIC will talk to the thin clients. Each NIC has an IP number that is its address. The IP address can be assigned by another computer in some way or a person can give it a static IP address that
- Download the LTSP software -- use apt get from the terminal window
- Install the LTSP software and reboot
- Change the startup sequence in the thin client you want to attach to your newly rebooted server to start from the network card.
- Connect !!
Changing or assigning an IP number to a NIC
- Look for Network settings or Network configuration (usually have to Unlock)
- Look where the address can be made static. change
For homework: Install the lamp, wamp, mamp -- contains the webserver, database, and information needed to run the programs/scripts (php).
- Apache -- webserver -- allows other computers to attach and see webpages from your computer
- MySQL -- database - this allows for storage of users, courses, grades, etc for the moodle
- PHP -- allows the instructions that display the webpages and interacts with the database.
September 17
Permissions:
- permissions allow access to files and folders
- you can see permissions in linux by typing ls -l on the command line in a terminal
- each file can have permissions for Owner, Group, and World
- permissions can have read, write, and/or execute (run) access
- when reading permissions the first set of permissions is owner (you if they are your files), middle is group and last onesare world (everyone).
- a file as follows would have read write execute permissions for owner with no access to groups or the world rwx------ (note dashes mean no permission)
- a file as follows would have read, write, execute permission for owner and read and execute permissions for the group. rwxr-x--- (they can read it.. and run it.. but cant change it)
- a file with permission of rwxrwxrwx would allow anyone to do anything with the file
- permissions can also be represented by a group of 3 numbers such a 751 with the first number being owner (the 7 in the example) the middle number being group (5) and the last number being the world (1)
- To calculate the numbers r = 4, w= 2 and x = 1. therefore rwx = 7 r-x = 5 r--4 and x = 1
- rwx------ = 700 rwxr-x--- = 750 rwxr-xr-x = 755 (common for web siites)
Command line commands summary (aka people cant afford to buy vowels)
- ls - list files in the current folder
- ls -l - list files in the current folder and give details about them
- cd foldername change directory (or folder) to another folder
- less - display contents of the file on the screen
- sudo - go into supervisor mode to allow to do administrative commands
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Common Folders in Linux (Unix)
- home -- all users will have folders in here usually
- etc -- contains program information and configuration files
- var -- contains web server and error and information logs
Configuration files
- have .conf extension
- contain informaton needed by the program such as data folder paths, how big files can be, etc
- are how you customize a program for YOUR computer to match your file paths and settings
TCP/IP and Sending information via the Internet (aka YOU'VE GOT MAIL)
The OSI model is used to send information over a network. In the term TCP/IP TCP is the how things are packaged up to transport and the IP is the address to go to. There are 7 layers in the OSI model that get things moving and what follows is a bit of an over simplification yet should help with concept.
To send an email over the web it might go something like this.
Package it up
- Layer 7 --- what are we sending today and what program is it in... ?? ok we're doing tmail
- Layer 6 --- how is it going to be packaged up? is it too big to send as one packet and do we need to make it go in a secret code? (encrypt it). Most information going across the web are BUNCHES of different little packets-- like you only have small envelopes and if you have too much stuff to mail you have to use more than one envelope.. most emails have way more than one envelope.
- Layer 5 --- do we have to translate it... (some computers talk in one way and another computer may talk another way (different protocols) ... this layer can convert between the two)
- Layer 4 --- Its all packaged and converted... ok lets dispatch it.. This layer keeps checking the receiving end until all the packets (envelopes) arrive. If one gets "lost in the mail" it will send a duplicate copy of it.
Those layers are the host layers that the computers do.... NOW for the tough stuff.. the actual moving of the packets (trucking or air express the envelopes)
Deliver it
- Layer 3 -- routing the packets. eg.. ok .. these envelopes are in Knoxville, have to go to San Francisco. We ended up with 20 envelopes -- ok . 10 of them can go to dallas on truck A then split them into 5 and 5 on Trucks C and D...to get them to SF. The other 10 can go to denver and then on to SF
- Layer 2 -- monitors the transmission of each packet. . doest worry about all 20 envelopes.. Simply tracks a single truck
- Layer 1 -- defines the physical bit transport.. ie.. how big is the truck. etc
So what happens is all the layers work together.. and when Layer 4 tells the receiving computer (ie talks to SF and all envelopes have gotten there..) then the recieving computer says.. You've Got Mail
