XK0-006 System Management Practice Test 3 — 15 Questions

Question 1

Which command displays the number of lines, words, and characters in a file?

Accepted Answer

wc file.txt. The `wc` command without any options displays the number of lines, words, and characters in a file, in that order. By default, `wc` counts newline characters (lines), whitespace-delimited tokens (words), and bytes (characters) in the specified file. This makes option A the correct choice for displaying all three counts.

Answer

wc -w file.txt

Answer

cat file.txt | wc -l

Answer

stat file.txt

Question 2

A Linux administrator needs to add an ACL entry to grant read permission to a user named 'jdoe' on a file. Which TWO commands can be used to achieve this? (Select TWO).

Accepted Answer

setfacl -m u:jdoe:r file. Both setfacl -m and setfacl --modify can be used to modify ACLs. The -m option is the short form, and --modify is the long form.

Answer

chown jdoe file

Answer

setfacl -x u:jdoe file

Answer

chmod u+r file

Question 3

A system administrator is working with compressed files. Which THREE commands can be used to view their contents? (Select THREE).

Accepted Answer

zgrep. The commands zgrep, zcat, and zless are used to search, concatenate, and view compressed files respectively. They are analogous to grep, cat, and less but work on compressed files. The other options, cat and less, do not handle compressed files directly.

Answer

cat

Answer

less

Question 4

A Linux administrator wants to search for the pattern 'ERROR' in all files under /var/log, ignoring case, and display line numbers. Which THREE options should be used with the grep command? (Select THREE).

Accepted Answer

-i. grep -r for recursive, -i for case-insensitive, -n for line numbers.

Answer

-c

Answer

-v

Question 5

Which command is used to display the current process hierarchy in a tree format?

Accepted Answer

pstree. ps aux shows all processes with details, but pstree shows them in a tree format, which is useful for visualizing parent-child relationships.

Answer

lsproc

Answer

ps aux

Answer

top

Question 6

A Linux administrator needs to find all files in /var/log that have been modified within the last 7 days and are larger than 10 MB. Which find command accomplishes this?

Accepted Answer

find /var/log -mtime -7 -size +10M. Both commands correctly find files modified within the last 7 days and larger than 10 MB. Option A uses -mtime -7 (modified less than 7 days ago) and option D uses -mmin -10080 (modified less than 10080 minutes ago, which is equivalent to 7 days). Both use -size +10M for files larger than 10 MB.

Answer

find /var/log -atime -7 -size +10M

Answer

find /var/log -mtime +7 -size -10M

Question 7

Given an ACL entry 'u:john:rwx' on a file, which command would remove only the ACL entry for user john without affecting other ACL entries?

Accepted Answer

setfacl -x u:john /path/to/file. setfacl -x removes a specific ACL entry. The syntax 'u:john' removes the ACL for user john.

Answer

setfacl -k /path/to/file

Answer

setfacl -m u:john:- /path/to/file

Answer

setfacl -b /path/to/file

Question 8

A system administrator wants to change the priority of a running process with PID 1234 to a lower priority (higher nice value). Which command should be used?

Accepted Answer

renice -n 10 -p 1234. renice is used to change the nice value of an existing process. A higher nice value means lower priority.

Answer

renice -n -10 -p 1234

Answer

chrt -p 10 1234

Answer

nice -n 10 -p 1234

Question 9

Which of the following directories is defined by the Filesystem Hierarchy Standard (FHS) as containing essential user command binaries that need to be available in single-user mode?

Accepted Answer

/bin. /bin contains essential command binaries required for booting and single-user mode.

Answer

/sbin

Answer

/opt/bin

Answer

/usr/bin

Question 10

An administrator needs to find the line number of the first occurrence of the string 'ERROR' in a log file, ignoring case. Which command is most appropriate?

Accepted Answer

grep -in 'error' logfile. grep -in 'error' logfile will output the line numbers with matches, ignoring case. The first line will be shown first if no other sorting is applied.

Answer

grep -n 'ERROR' logfile

Answer

sed -n '/ERROR/=' logfile

Answer

awk '/ERROR/ {print NR}' logfile

Question 11

A technician is troubleshooting a service that fails to start at boot. Which systemctl command should be used to ensure the service starts automatically on subsequent boots?

Accepted Answer

systemctl enable service. systemctl enable creates symlinks so the service starts at boot. The status shown by is-enabled confirms if it is enabled.

Answer

systemctl mask service

Answer

systemctl start service

Answer

systemctl reenable service

Question 12

A file has permissions rwxr-x--- and is owned by user alice and group devs. Which command would add the SUID bit while preserving existing permissions?

Accepted Answer

chmod u+s file. chmod u+s adds the SUID bit. The symbolic mode 'u+s' sets the SUID without changing the existing permission bits.

Answer

chmod a+s file

Answer

chmod 2755 file

Answer

chmod 4750 file

Question 13

Which command is used to display the contents of the systemd journal for a specific unit?

Accepted Answer

journalctl -u. journalctl -u unitname displays logs for the specified systemd unit.

Answer

systemctl status unit

Answer

dmesg

Answer

journalctl -f

Question 14

An administrator needs to replace all occurrences of '192.168.1.1' with '10.0.0.1' in a configuration file named config.txt. Which sed command should be used to perform an in-place edit?

Accepted Answer

sed -i 's/192.168.1.1/10.0.0.1/g' config.txt. sed -i 's/192.168.1.1/10.0.0.1/g' config.txt performs global replacement in-place.

Answer

sed -i 's/192.168.1.1/10.0.0.1/' config.txt

Answer

sed -e 's/192.168.1.1/10.0.0.1/g' config.txt

Answer

sed 's/192.168.1.1/10.0.0.1/g' config.txt > config.txt

Question 15

A technician wants to create a symbolic link in /usr/local/bin that points to /opt/myapp/bin/start.sh. The technician has write permissions to /usr/local/bin. Which command should be used?

Accepted Answer

ln -s /opt/myapp/bin/start.sh /usr/local/bin/start.sh. ln -s target linkname creates a symbolic link. The target should be the file to link to, and the link name is the new symlink.

Answer

ln -s /usr/local/bin/start.sh /opt/myapp/bin/start.sh

Answer

ln /opt/myapp/bin/start.sh /usr/local/bin/start.sh

Answer

cp -s /opt/myapp/bin/start.sh /usr/local/bin/start.sh