EX200 Practice Test 10 — 10 Questions

Question 1

A script needs to be run at system boot for a specific user. Which method ensures the script runs with that user's environment?

Accepted Answer

Create a systemd user unit in ~/.config/systemd/user/. Systemd user units, placed in ~/.config/systemd/user/, are executed in the user's own session context, inheriting the user's environment variables, PATH, and D-Bus session. This ensures the script runs with the specific user's environment at boot, as systemd starts the user manager (systemd --user) early in the boot process for each enabled user.

Answer

Place the script in /etc/rc.d/rc.local

Answer

Add an entry to ~/.xprofile

Answer

Add the script to the user's crontab with @reboot

Question 2

A system administrator is troubleshooting a container that fails to start with the error: 'Error: cannot start container: listen tcp4 :80: bind: address already in use'. The container is intended to serve HTTP traffic on port 80. What is the most appropriate first step to resolve this issue?

Accepted Answer

Check which process is using port 80 and either stop that process or use a different host port. The error 'address already in use' indicates that port 80 on the host is already occupied by another process. The correct first step is to identify that process using commands like `ss -tlnp` or `lsof -i :80` and either stop it or map the container to a different host port (e.g., `-p 8080:80`). This directly resolves the binding conflict without risking data loss or unintended behavior.

Answer

Add --force to the podman run command

Answer

Add --replace to the podman run command

Answer

Use --net=host to bypass the port mapping

Question 3

Which THREE options to podman run can be used to publish container ports to the host? (Select exactly three.)

Accepted Answer

-p. (-p) is correct because it is the short form of --publish, which maps a container port to a host port. Option B (--publish) is the long form of -p and explicitly publishes container ports to the host. Option D (-P) is correct because it publishes all exposed container ports to random high-numbered ports on the host (typically in the range 32768-60999).

Answer

--expose

Answer

--port

Question 4

Refer to the exhibit. A user named 'carol' has been added to the system with the command useradd -G wheel carol. Which line in /etc/group will confirm that carol is now a member of the wheel group?

Accepted Answer

wheel:x:10:root,alice,bob,carol. The `useradd -G wheel carol` command adds 'carol' to the supplementary group 'wheel', and the `/etc/group` file lists supplementary members as a comma-separated list with no trailing comma. The line `wheel:x:10:root,alice,bob,carol` shows 'carol' appended after the existing members, which matches the expected format.

Answer

wheel:x:10:carol,root,alice,bob

Answer

wheel:x:10:root,alice,bob,carol,

Answer

wheel:x:10:root,alice,bob carol

Question 5

A developer runs the script shown in the exhibit and always sees 'Success' printed, even when the previous command fails. What is the most likely cause?

Accepted Answer

The $? variable captures the exit status of the [[ command, not the intended command. The `[[ ]]` conditional construct is a shell keyword that itself produces an exit status. When `$?` is checked immediately after `[[ ]]`, it captures the exit status of the `[[ ]]` evaluation (which is 0 if the condition is true, 1 if false), not the exit status of the command that was run before the `[[ ]]`. Since the developer always sees 'Success' printed, the `[[ ]]` condition must be evaluating to true (exit status 0), causing `$?` to be 0 and the script to always take the success path, regardless of the actual previous command's result.

Answer

The [[ ]] syntax always evaluates to true

Answer

The $? variable is only set after external commands, not builtins

Answer

The $? variable always returns 0 in a conditional

Question 6

A new employee named asmith needs a user account with a home directory and a specific UID of 1500. Which command accomplishes this?

Accepted Answer

useradd -m -u 1500 asmith. `useradd -m -u 1500 asmith` creates the user asmith with a home directory (via `-m`) and assigns a specific UID of 1500 (via `-u`). The `-m` flag ensures the home directory is created if it does not exist, which is required by the question.

Answer

adduser -uid 1500 asmith

Answer

useradd -h /home/asmith -u 1500 asmith

Answer

useradd -d /home/asmith -U 1500 asmith

Question 7

An administrator wants to ensure that any new user accounts created on the system have a default primary group matching the username. What change is needed?

Accepted Answer

Set USERGROUPS_ENAB to yes in /etc/login.defs. Setting USERGROUPS_ENAB to yes in /etc/login.defs instructs the useradd command to automatically create a private group with the same name as the new user and assign it as the user's primary group. This is the default behavior in Red Hat Enterprise Linux and ensures that each new user has a matching primary group without manual intervention.

Answer

Set GROUP to same name in /etc/default/useradd

Answer

Set USERGROUPS_ENAB to no; then create user with -g

Answer

Set CREATE_HOME to yes in /etc/login.defs

Question 8

Refer to the exhibit. An administrator attempts to mount all filesystems using 'mount -a' and receives an error. What is the most likely cause?

Accepted Answer

The entry for /dev/vdb1 in /etc/fstab uses a device name that does not exist.. The error occurs because the entry in /etc/fstab for /dev/vdb1 references a device name that does not exist on the system. When 'mount -a' is executed, it reads /etc/fstab and attempts to mount each filesystem; if the device node is missing (e.g., due to a typo, incorrect kernel name, or the device not being attached), the mount fails with an error like 'mount: special device /dev/vdb1 does not exist'. This is the most likely cause given the scenario.

Answer

The ext4 filesystem on /dev/vdb1 is corrupted.

Answer

The filesystem type specified in /etc/fstab is incorrect.

Answer

The mount point /mnt/data does not exist.

Question 9

A system administrator needs to change the primary group of an existing user to a group that already exists. Which command should be used?

Accepted Answer

usermod -g existinggroup username. The `usermod -g` command changes the primary group of an existing user to a specified group that already exists on the system. The `-g` option sets the initial login group (GID) for the user, which must be a valid group name or GID from `/etc/group`.

Answer

groupmod -g existinggroup username

Answer

usermod -p existinggroup username

Answer

usermod -G existinggroup username

Question 10

A server has been compromised, and the administrator suspects an unauthorized user account may have been created. Which file should be examined to list all local user accounts?

Accepted Answer

/etc/passwd. The /etc/passwd file is the primary local user account database on Linux systems, listing all user accounts with fields such as username, UID, GID, GECOS, home directory, and login shell. Examining this file reveals every local user account, including any unauthorized ones that may have been created, because each account must have an entry here to be recognized by the system.

Answer

/etc/shadow

Answer

/etc/shells

Answer

/etc/login.defs