102-500 Online Practice Questions and Answers

When the command echo $$ outputs 12942, what is the meaning of 12942?

A. It is the process ID of the echo command.

B. It is the process ID of the current shell.

C. It is the process ID of the last command executed.

D. It is the process ID of the last command which has been placed in the background.

What benefit does an alias in bash provide?

A. It provides faster lookups for commands in the system directory.

B. It creates a local copy of a file from another directory.

C. It hides what command you are running from others.

D. It allows a string to be substituted for the first word of a simple command.

Which of the following are requirements in order to run a shell script like a regular command from anywhere in the filesystem? (Choose THREE correct answers.)

A. The user issuing the command must be in the group script.

B. The script file must be found in the $PATH.

C. The script file must have the executable permission bit set.

D. The script must begin with a shebang-line (#!) that points to the correct interpreter.

E. The file system on which the script resides must be mounted with the option scripts.

Which of the following SQL queries counts the number of occurrences for each value of the field order_type in the table orders?

A. SELECT order_type,COUNT(*) FROM orders WHERE order_type=order_type;

B. SELECT order_type,COUNT(*) FROM orders GROUP BY order_type;

C. COUNT(SELECT order_type FROM orders);

D. SELECT COUNT(*) FROM orders ORDER BY order_type;

E. SELECT AUTO_COUNT FROM orders COUNT order_type;

On a system running the KDE Display Manager, when is the /etc/kde4/kdm/Xreset script automatically executed?

A. When KDM starts

B. When a user's X session exits

C. When KDM crashes

D. When X is restarted

E. When X crashes

To prevent a specific user from scheduling tasks with at, what should the administrator do?

A. Add the specific user to /etc/at.allow file.

B. Add the specific user to [deny] section in the /etc/atd.conf file.

C. Add the specific user to /etc/at.deny file.

D. Add the specific user to nojobs group.

E. Run the following: atd --deny [user].

Which command will set the local machine's timezone to UTC?

A. cat UTC > /etc/timezone

B. ln -s /usr/share/zoneinfo/UTC /etc/localtime

C. date --timezone=UTC

D. mv /usr/timezone/UTC /etc

Which of the following tools used for DNS debugging, reports not only the response from the name server but also details about the query?

A. dnsq

B. dig

C. hostname

D. dnslookup

E. zoneinfo

Which configuration file contains the default options for SSH clients?

A. /etc/ssh/sshd_config

B. /etc/ssh/ssh

C. /etc/ssh/ssh_config

D. /etc/ssh/client

E. /etc/ssh/ssh_client

Which of the following tasks can the date command accomplish? (Choose two.)

A. Set the system's date and time.

B. Set the system's date but not the time.

C. Calculate the time span between two dates.

D. Print a calendar for a month or a year.

E. Display time in a specific format.