DevNet Associate 1.2.3 Quiz Module 1 Quiz – Linux Review (Answers)
1. What Linux command is used to display the contents of the current directory?
- pwd
- cat
- ln
- ls
Explanation: The Linux ls command, without any options, is used to display the contents, such as files and subdirectories, of the current directory.
2. What command is used to rename a file in a Linux system?
- mv
- dd
- cp
- rm
Explanation: The mv Linux command can be used to move a file to another directory or rename a file. The cp command is used to make a copy of files or directories. The dd command is also used to make a copy of a file. The rm command is used to delete a file.
3. A user issues a Linux command and the result is shown.
total 40 drwxr-xr-x 2 devasc devasc 4096 Apr 15 19:09 Videos drwxr-xr-x 2 devasc devasc 4096 Apr 15 19:09 Templates drwxr-xr-x 5 devasc devasc 4096 Mar 30 21:24 snap drwxr-xr-x 2 devasc devasc 4096 Apr 15 19:09 Public drwxr-xr-x 2 devasc devasc 4096 Apr 15 19:09 Pictures drwxr-xr-x 2 devasc devasc 4096 Apr 15 19:09 Music drwxr-xr-x 5 devasc devasc 4096 Mar 30 21:21 labs drwxr-xr-x 2 devasc devasc 4096 Apr 15 19:09 Downloads drwxr-xr-x 2 devasc devasc 4096 Apr 15 19:09 Documents drwxr-xr-x 2 devasc devasc 4096 Mar 30 21:25 Desktop devasc@labvm:~$
Which Linux command is used to display the contents of the current directory as shown?
- ls -l
- ls -a
- ls -lr
- ln
Explanation: The Linux ls command with the -l option is used to display contents in the current directory as a “long list”. By default, the listing is sorted alphabetically. With both the -l and -r options specified, the listing is displayed as a long list and in reverse order.
4. A system administrator of a Linux server is searching the passwd file for the username taylor that appears at the beginning of the line. Which grep command should the administrator use?
- grep taylor /etc/passwd
- grep ‘.taylor’ /etc/passwd
- grep ‘^taylor’ /etc/passwd
- grep ‘[taylor]’ /etc/passwd
Explanation: The Linux grep command can be used to process text line by line and to print any lines which match a specified pattern. The matching patterns are based on regular expression (regex) query modifiers used to select the appropriate content. Some regex query modifiers are as follows:
(underscore): matches a space
^ (caret): indicates the start of a string
$ (dollar sign): indicates the end of a string
. (period): matches a single character, including a space
(asterisk): matches zero or more occurrences of the preceding character
(square bracket): matches a character
{ } (curly bracket): repeats preceding character
5. A user issues the apt-get upgrade command to update system files in a Ubuntu Linux system and receives an error message of “permission denied.” What should the user do to complete the task?
- Issue the allow apt-get upgrade command.
- Issue the sudo apt-get install command.
- Issue the apt-get install –allow command.
- Issue the sudo apt-get upgrade command.
Explanation: There are several Linux commands in the Advanced Package Tool (APT) system to perform software package management tasks. The apt-get upgrade command is used to update all packages and dependencies on the system. This command must be run with administrative level permissions, which are provided by the sudo command.