1. Open VirtualBox and start your linux VM. Boot the machine and log in with the user account you created in Lab #1. Open the Terminal application.

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1 CIT 210L Name: Lab #2 1. Open VirtualBox and start your linux VM. Boot the machine and log in with the user account you created in Lab #1. Open the Terminal application. 2. Listing installed packages - Before you can update packages on a system, it is first useful to see which packages are installed. Yum contains a "list" option to display the list of installed packages. When invoked without arguments, list will show all packages installed: yum list yum list more yum list wc -l How many packages are installed The more part of that command pipes the output of yum list to the more command. A pipe ( ) passes the output of the first command to the input of the second. In this specific case, what does piping output to more give you? Package description - It is sometimes useful to get a description of what a package is. This can be accomplished by passing a package name to the yum "info" option: yum info rpm This gives information on the rpm package.

2 3. Installing and removing packages - The real heart of a package manager is it's ability to install packages, remove packages, and to handle the dependencies that are associated with a specific release of a package. Yum allows packages to be installed with the "install" option, which takes one or more packages to install as arguments. yum install htop and yum remove htop Now is a good time to re-install htop (for a future lab). When you run the command yum install htop what is shown on the screen? Describe briefly Now switch to root by typing su and Enter, and then entering the root password. Reexecute this command as the root user to install htop. 4. Checking for updates - One of yum's nicest features is its ability to install packages from remote repositories, and to compare the currently installed packages with what is available remotely. Run the command yum check update How many updates did your system need? To save lab time, do not perform the update. List a few (no more than 5) of the updates.

3 To update all of the outdated packages to newer versions, yum can be run with the "update" option. this may take a very long time yum update To update a single package (for example, htop) yum update htop Pick one of the updates your system needs (from above) and update it. Which did you pick? 5. Then type exit and Enter to log out of root. This will place you back in the user session you started in. 6. At the command prompt, type pwd (which stands for print working directory ) and hit enter. This will tell you what directory you are currently in. Write down the response here 7. Type man pwd and hit enter. The man command stands for manual and will tell you how a specific command is used, and what it does. Here you have accessed the man page (or manual page) for the command pwd. You can use the arrow-keys to scroll up and down within a man page and use the letter q to quit when you are finished reading the man page. On the man page for pwd (which you are looking at), what does the first sentence under DESCRIPTION say? 8. After returning to the command-prompt, type man man and hit enter. What does this command do? Please explain in your own words

4 9. To list the files in your current directory, type ls (lower-case LS or the list command) and hit enter. What files are in your present working directory? 10. Type the command cd.. (cd followed by a space, then two periods) and hit enter. This will take you into the directory above. ( cd = change directory,.. = parent directory, and. = current directory) Type pwd and hit enter again. What directory are you in now? 11. Type ls again. This will list all the files and directories in your present directory separated by white space. How many files/directories exist in your present working directory? 12. Type ls l (ls followed by a space, a hyphen, and another lower-case L). This gives the long-listing format, which is a more detailed list. For every file and directory in your present working directory, you should see something like this: drwxr-x--x 3 root root :22 myname The fields are as follows permissions link-count file-owner file-group size(bytes) last-modified-date filename The permissions field will start with a d if the file is a directory, an l if the file is a soft-link, and a - if the file is a regular file. Do not worry about the rest of the permissions, the linkcount, the file-owner and file-group for now. You should be able to easily determine how large a file is, when it was last modified, and what its name is from this info. You should also know whether a file listed by ls l is a normal file or a directory.

5 13. Use the su command to become root again. Change directory to /root by typing cd /root and hitting enter. Now type ls l and hit enter. a. Is anaconda-ks.cfg a regular file or a directory? b. When was it last modified? Congratulations! Lab #2 is complete. J