Linux Operations and Administration

Review Questions

1. 
   Which of the following directories should you back up regularly? (Choose all that apply.)
   

b. /home

2. 
   An employee named Andrea wants to back up an entire home directory in a file. Which of the following commands should be used?
   

3. 
   Which of the following commands should you use to list all members in the project.tar archive?
   

4. 
   An employee complains that her home directory has disappeared. Which of the following commands should you use to extract the backup archive of her home directory?
   

5. 
   Which of the following options is used with the tar utility to add members to an archive?
   

6. 
   Explain the purpose of a snapshot file.
   

7. 
   Explain the difference between full and incremental backups.
   

8. 
   Which of the following cpio modes is used when creating an archive?
   

9. 
   Which of the following cpio modes is used when copying files from one directory tree to another without creating an archive?
   

10. 
    Your company has a tight budget, and you have been asked to create tar archives to save space on the backup medium. Which of the following commands enables you to archive home directories and compress them at the same time?
    

11. 
    Describe the first five fields of the cron table.
    

    Field	Allowed values
    1: Minute	0–59
    2: Hour	0–23
    3: Day of the month	1–31
    4: Month	1–12
    5: Day of the week	0–6; 0 is Sunday and 6 is Saturday

12. 
    What’s the difference between a user cron table and a system cron table?
    

Activities

Step 4: Students should see the tar file; it should be 10240.

Step 5: Yes.

Step 7: Yes, the three files should be back, and the tar file should still be there because the tar utility doesn’t overwrite files. Instead, it makes a copy of the file and uses the copy as a member in the archive.

Step 7: Yes, the member stars is added to the archive because of the command in Step 6.

Step 9: The sun member was changed because content was added to the file in Step 8.

Step 15: The flower and moon members have been deleted from the archive.

Step 5: Students’ answers should be similar to the following:

-rw-r--r-- username/users 0 2012-04-26 19:07 blue

-rw-r--r-- username/users 0 2012-04-26 19:07 red

-rw-r--r-- username/users 0 2012-04-26 19:07 white

Step 7: They’re different because the --mode=777 option was used in Step 6. The members in file2.tar have rwx permissions for each category.

Step 8: The members are english, math, and history.

Step 13: Yes, they should all be restored.

Activity 6-5

Step 5: The ls -l command displays the following:

-rw-r--r-- 1 username users 512 2012-05-10 18:54 act6.5.cpio

-rw-r--r-- 1 username users 0 2012-05-10 18:53 strong

-rw-r--r-- 1 username users 0 2012-05-10 18:53 stronger

-rw-r--r-- 1 username users 0 2012-05-10 18:53 strongest

Step 7: The tilde (~) symbol represents the absolute path to the user's home directory.

Step 9: After all files are passed from the dir1 directory to the dir2 directory, the ls -l command displays the following:

-rw-r--r-- 1 username users 0 2012-05-10 18:57 act6.5.cpio

drwxr-xr-x 2 username users 4096 2012-05-10 18:57 dir2

-rw-r--r-- 1 username users 0 2012-05-10 18:57 strong

-rw-r--r-- 1 username users 0 2012-05-10 18:57 stronger

-rw-r--r-- 1 username users 0 2012-05-10 18:57 strongest

Activity 6-6

Step 3: The ls -l command displays the following:

-rw-r--r-- 1 username users 18202 2012-04-25 18:40 gzip.man

-rw-r--r-- 1 username users 15438 2012-04-25 18:40 tar.man

Step 5: Compression ratio is 67.8%. The size of tar.man.gz is 5012.

Step 7: For tar.man, it’s 67.7%; for gzip.man, it’s 65.2%.

Step 3: The ls -l command displays the following:

-rw-r--r-- 1 username users 18202 2012-04-25 18:40 gzip.man

-rw-r--r-- 1 username users 15438 2012-04-25 18:40 tar.man

Step 4: Students should get the following result:

The size of the gzip.man.bz2 file is 5885

Step 6: Students should get the following result:

gzip.man: 3.093:1, 2.587 bits/byte, 67.67% saved, 18202 in, 5885 out

bzip2.man: 2.938:1, 2.723 bits/byte, 65.96% saved, 18668 in, 6354 out

Activity 6-8

Step 2: An empty cron table should be displayed, unless the student has created a user crontab table on the machine as that user.

Step 6: The new cron table should be displayed.

Case Projects

The command should look like the following: