Lab 3 Warnings / Debrief

Preparing for Lab 3

Purpose of Lab3

In this lab, you are going to identify potential problems such as not properly compressing VM image files when backing up VMs, or forgetting your root password. You will also learn to conserve hard disk space by learning how to compress and decompress files that are stored on your computer server. In addition, you will learn alternative methods of how to install applications (i.e. programs).

Main Objectives

• Learn to troubleshoot some common problems after installing VMs
• Create and extract archive files (tar and tar.gz)
• Install applications using various methods:

• Download, decompress and archive file from the Internet, then compile source code in order to install an application.
• Use yum utility to install software from local source programs (on DVD drive)
• Use yum utility to install software from repositories (online storage areas)
• Learn how to add repositories (online software storage areas) to install less common applications.

• Demonstrate the use of Bash Shell scripts to automate routine tasks (generate a customized software report)

Rescuing Your System

Press e at Grub Boot Menu to edit

There are a few "classic problems" that students can encounter with their virtual machines and their host machine after performing lab2. Although all OPS235 students may not encounter these problems, it is good to be aware of what a potential problem may look like, and know how to solve that problem.

A few common problems are:

• I Can't boot into Graphical Mode on my c7host machine
• I Forgot My Regular User Password
• I Forgot My root Password
• I Can't Start My Virtual Machine
• I Can't start my Host machine

Troubleshooting consists of 3 basic elements:

• Asking Questions (eg. what was done recently prior to problem?)
• Eliminating what the problem IS NOT
• Tenacity and patience (ability to focus on finding the cause of the problem)

If you cannot log graphically into your machine (first 3 common problems), there is a trick to boot your system into single-user mode. This mode does not provide networking, graphics, or logging in as other regular users, but can connect to a text-based interface as the root user. This method will only work if a GRUB (Grand Unified Boot-loader) password has not been set, or that you haven't forgotten the GRUB password.

Common Mistakes / Warnings

Be Aware of the Following Issues
Be aware of these common mistakes that students make that can cause problems for their future labs.

Preparing for Lab Sign-Off

Students should be prepared with all required commands (system information) displayed in a terminal (or multiple terminals) prior to calling the instructor for signoff.

In order to properly complete your lab and move to the next lab, you must have your instructor "sign-off" on your lab

• Each "signed-off" lab (before due date) is worth 1% of your final grade.
• Signing-off on labs help to spot errors that can cause problems with future labs.
• Do you ask the instructor what to check for! Read at the bottom of the lab the requirements, and have all proof available for instructor to view at same time.
• Failing to be prepared and asking instructor what to check when assignment is mark will result in deduct of marks!
• For example, open multiple terminals with command results. If properly set-up ahead of sign-off, the process should only take instructor approx 20 seconds to sign-off your lab.
• If you do not have your lab-logbook, you MUST show your work and your lab log-book to your instructor for sign-off in the next class. This may cause a late penalty if past the required due date.