Transcript Chapter 2 2007

2: Operating Systems
Networking for Home & Small Business
Purpose of the OS
• Allows components to work together
• Write a report & print
– Enter on keyboard
– Stored in RAM
– Processed by CPU
– Displayed on monitor
– Printed on printer
• All computerized device require an OS
How the OS Works
• Loads OS into RAM from disk drive
• Shell
– Interface with the applications & user
– Provides access to the OS
• Interact with the shell using
– Command Line Interface (CLI)
– Graphical User Interface (GUI)
• Kernel
– OS code that interacts with the computer hardware is
known as the
– Manages communication between hardware &
software
The OS
CLI
GUI
The OS
• Manage one user at a time
• Multitask
– OS keeps track of resources used
• Some resources are not directly connected
to the PC
– Examples???
Redirector & NOS
• Redirector (OS driver or Network Client software)
• Now becomes a NOS
– Allows device to be shared
– Acts as though it were directly connected
Review so far…
• Which interface has a command prompt?
– CLI
• After powering up, the OS gets loaded into
where?
– RAM
• What interfaces with the user &
application?
– Shell
OS License
• Commercial License
• Windows, Mac, UNIX
• GNU Public License (GPL)
– FREE
• Linux
Comparing Licenses
Commercial
License
GPL
Access
Restricts/limits
access to code
Access to code &
can enhance it
Cost
Expensive $$$
Free
Windows, Mac, Unix;
license each PC
Development
Cycle
Structured; changes
aren’t avail quickly
Ongoing, changes
distributed quickly
Support
Avail for a fee
usually
Mostly community
support
OS Requirements
•
•
•
•
Amount of RAM
Hard disk space required
Processor type and speed
Video resolution
• Minimum
– Poor performance
• Recommended
Activity- Commercial or GPL
Choosing An OS
• Must meet requirements of user
– Support applications
– Security sufficient
•
•
•
•
Is the hardware supported by the OS?
Will the company support the new OS?
At home, will support be available readily?
Total Cost of Ownership (TCO)
– Buying, installing, supporting
Review
1. Which type of OS provides full access to
the source code?
– GPL
2. Which type of OS is costly?
– Commercial
3. Which type of OS provides support
through its users?
– GPL
Review
1. Name 4 specifications for OS install
requirements.
–
–
–
–
HD
Processor
RAM
Video Resolution
2. Describe a network redirector.
3. What are the 2 ways you can interact with
the shell?
– CLI & GUI
Lab 2.2
• Specifications of OS
Installing the OS- Clean Install
• Deletes all data on install path
• Applications need to be reinstalled
• When would you do a clean install?
Installing the OS- Upgrade
• System config settings, applications and
data are preserved
• Replaces old OS files with new ones
Installing the OS- Multi-boot
• Can install more than one OS to a drive
• Why?
• Each has its own partition
– Own files & config settings
• On start, user chooses which OS
• Only one OS runs at a time
Activity
Pre-Installation Checklist
1. Verify all hardware is certified to work with the OS.
2. Verify the hardware resources meet or exceed the minimum
requirements.
3. Confirm the appropriate installation medium is available. Do you
have CD or DVD & the correct drive?
4. If the OS is to be installed on a system that already contains data:
(a) Use system diagnostic tools and utilities to ensure the current
OS installation is in good condition, free of malicious or damaging
files and codes; (b) Complete a full backup of all important files.
5. If performing a clean-install, verify that all application software is
available for installation.
Partitions
• On clean install,
some techs…
– Partition 1 for OS
– Partition 2 for data
• When upgrade OS,
data will not be
deleted
Review so far…
1. What is a partition?
2. What happens to data on a HD during a clean
install?
3. How many OS’s are running in a multiboot
system?
4. What happens to applications during an
upgrade?
Configure for Network
• What is a network?
– Group of devices
connected to each
other to share info &
resources
• NIC
• IP Address
– Id’s computer UNIQUE
• Subnet Mask
– Id’s the network it is on
• Default Gateway
– the way out of the
network
Network Communication
Configuring the IP
• Manual (static) or Dynamic (automatic) pool
Computer Naming
• Manually assigned
• For easy sharing
• Admin designs
naming scheme
• PRT-CL-Eng-01
represents the 1st
color laser printer in
the Engineering
Department
Planning Names & Addresses
• The larger the network gets, you MUST be
organized & documented!
• Come up with guidelines
Review
1. A DHCP server assigns address how?
– Automatically/Dynamically
2. What are 3 settings you need to connect
to a network?
– IP, Subnet Mask, Default Gateway
3. What is a default gateway?
– Address to get out of the network so it can
communicate with other networks
4. Describe a partition.
Review
1. Which install method requires applications
to be reinstalled?
– Clean Install
2. Before upgrading the OS, what should
you do with your data?
– Back it up
3. To be on a network, what 2 things need to
be unique?
– IP address & computer name
When to Apply Patches
• What’s a patch?
– Piece of program code
that can correct a problem
or enhance the
functionality of an
application program or OS
• Update computers often
BUT make sure you
understand the patch
first!
Applying the OS Patch
• Automatic
installation
• Prompt for
Permission
• Manual
Auto, Manual, or Prompt?
Applying the Application Patch
• Browsers, Office, other programs
• Repair a detected vulnerability or other
problem
• Found on manufacturer’s site
Lab 2.3.3
Review
1. What’s a patch?
2. Where can you find a patch?
•
Manufacturer’s web site
3. What are the 3 methods for getting OS
updates?
•
Auto, Manual, With Permission
4. What user interface has icons?
•
GUI
Review
1. Where do devices get IP addresses from
dynamically?
– A server
2. What is needed to install two OS’s on a
PC?
– Multiple partitions
3. What letter grade will you get on this test?
– A or B, hopefully
2: Operating Systems
Networking for Home & Small Business