EX200 Practice Test 10 — 10 Questions

Question 1

An administrator is tasked with deploying a containerized application on a Red Hat Enterprise Linux 8 server that is part of a high-security environment. The application must run as a non-root user inside the container. The container image is based on Red Hat Universal Base Image (UBI) and exposes port 443 for HTTPS. The administrator needs to ensure that the container can be restarted automatically if it crashes and that the application logs are persisted on the host in /var/log/app. The application requires a configuration file that is generated dynamically at startup and must be accessible to the container. The administrator has created a systemd service file for the container but wants to use Podman's built-in features to manage the container. Which approach meets all requirements?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Run the container with 'podman run --restart=always -v /var/log/app:/var/log -p 443:443 myapp' and rely on the container's restart policy.. Podman's built-in restart policy (`--restart=always`) ensures the container restarts automatically after a crash without requiring systemd. The volume mount persists logs at /var/log/app on the host, and the port mapping exposes port 443. This approach uses Podman's native features as desired, meeting all requirements. Option A relies on a systemd service generated by Podman, which shifts management back to systemd instead of using Podman's built-in restart capability. Option B uses an invalid command. Option D uses `--restart=on-failure`, which only restarts on non-zero exit codes and may miss other crash scenarios.

Answer

Create a systemd service file using 'podman generate systemd' on a running container, then enable the service with 'systemctl enable --now container-myapp'. The container should be started with '--restart=always' and appropriate volume and port mappings.

Answer

Create a 'podman service' unit using 'podman service create' to manage the container with automatic restart and boot-start.

Answer

Use 'podman create --restart=on-failure -v /var/log/app:/var/log -p 443:443 myapp' and then start it with 'podman start'.

Question 2

An administrator writes a script to check disk usage and send an alert if usage exceeds 80%. The script uses 'df -h /' and parses the output. To maintain portability and avoid common pitfalls, which approach is recommended?

Accepted Answer

Use 'df / | awk 'NR==2 {print $5}' | tr -d '%'. It uses `df /` (without `-h`) to produce a stable, machine-parseable output where the fifth field (`$5`) is always the percentage used, and `awk` reliably extracts it. The `tr -d '%'` removes the percent sign for numeric comparison. This approach avoids the portability issues of parsing human-readable output from `df -h`, which can vary in column spacing and ordering across different Unix/Linux systems.

Answer

Use 'df -h / | tail -1 | sed 's/.* //' | tr -d '%'

Answer

Use 'df -h / | tail -1 | cut -d' ' -f5'

Answer

Use 'df -h / | grep -oP '\d+%'

Question 3

Refer to the exhibit. After mounting /dev/sdb1 with the noexec option, a script located at /mnt/data/test.file cannot be executed. What change will allow execution while maintaining security?

Accepted Answer

Change the mount option to exec in /etc/fstab and remount. The noexec mount option prevents execution of any binaries or scripts on the filesystem, regardless of file permissions. To allow execution while maintaining security, you must change the mount option to exec in /etc/fstab and remount the filesystem (e.g., mount -o remount,exec /mnt/data). This approach preserves other mount options and avoids the security risks of removing noexec globally.

Answer

Copy the script to /tmp and run from there

Answer

Use chmod +x /mnt/data/test.file

Answer

Remount without noexec and add setuid bit

Question 4

Refer to the exhibit. The administrator wants to add an additional 5GB to the /mnt/data filesystem. There is no unpartitioned space on /dev/sdb. Which is the correct procedure?

Accepted Answer

Use fdisk to delete and recreate /dev/sdb1 with larger size, run partprobe, then xfs_growfs /mnt/data.. The filesystem on /mnt/data is XFS (as shown in the exhibit), and XFS cannot be shrunk; it can only be grown. Since there is no unpartitioned space on /dev/sdb, the partition itself must be resized. The correct procedure is to delete and recreate the partition with a larger size using fdisk, inform the kernel of the change with partprobe, and then grow the XFS filesystem with xfs_growfs /mnt/data.

Answer

Use resize2fs /dev/sdb1 to expand filesystem.

Answer

Add a new disk, create a physical volume, extend volume group, and extend logical volume.

Answer

Use fdisk to delete and recreate /dev/sdb1 with larger size, then mount.

Question 5

An administrator needs to compress a directory containing subdirectories and files into a single archive file, with maximum compression, and exclude all '*.tmp' files. Which command should be used?

Accepted Answer

tar -cjvf archive.tar.bz2 --exclude='*.tmp' /path/to/dir. The question specifies 'maximum compression'. Among common tar compression methods, bzip2 (via the -j flag) typically provides better compression ratios than gzip (-z), though it is slower. Option C uses `tar -cjvf` with the `--exclude` option placed correctly before the source directory, which is the proper syntax for tar exclusions. This command creates a .tar.bz2 archive with maximum compression while excluding all *.tmp files. Option A uses gzip, which offers faster compression but lower ratios, making it incorrect for 'maximum compression'. Options B and D also fail: B has incorrect syntax (--exclude after the directory), and D omits the exclude option entirely.

Answer

tar -czvf archive.tar.gz --exclude='*.tmp' /path/to/dir

Answer

tar -czvf archive.tar.gz /path/to/dir --exclude='*.tmp'

Answer

tar -czvf archive.tar.gz /path/to/dir

Question 6

You maintain a script that performs a long-running task and must clean up temporary files if the script is interrupted. The script uses:

#!/bin/bash
tempfile=$(mktemp)
trap "rm -f $tempfile" EXIT
# long task
sleep 100

You notice that if the script receives SIGINT (Ctrl+C), the temporary file is not removed. Investigation shows that the trap on EXIT is not executed on SIGINT. Which modification should be made?

Accepted Answer

Add a trap for INT: `trap "rm -f $tempfile; exit" INT`.. The EXIT trap is only triggered on normal script termination (e.g., reaching the end or an explicit `exit`), not on signals like SIGINT. By adding a separate trap for INT that explicitly removes the temp file and calls `exit`, the cleanup runs even when the user presses Ctrl+C, ensuring the temporary file is deleted.

Answer

Move the trap inside a subshell: (trap ... EXIT; long task).

Answer

Change `trap ... EXIT` to `trap ... 0`.

Answer

Add `set -e` at the beginning of the script.

Question 7

Refer to the exhibit. What effect does the value INACTIVE=-1 have on newly created user accounts?

Accepted Answer

The password inactivity period is disabled.. The `INACTIVE=-1` setting in the `useradd -D` or `/etc/default/useradd` configuration disables the password inactivity period. This means that after a password expires, the account will not be locked due to inactivity, effectively turning off the inactivity timer. The value -1 is a special sentinel that indicates no inactivity period is enforced.

Answer

The account expires immediately.

Answer

Passwords never expire.

Answer

Account is disabled if password expires but user does not log in within -1 days (immediately).

Question 8

An administrator needs to ensure that a specific LVM logical volume is automatically mounted at boot with the 'noexec' option. Which configuration file and entry should be used?

Accepted Answer

/etc/fstab: /dev/vg/lv /mnt ext4 defaults,noexec 0 0. /etc/fstab is the standard configuration file for defining filesystem mount points and options that are applied automatically at boot. The entry specifies the logical volume device, mount point, filesystem type, and mount options including 'noexec' to prevent execution of binaries on that filesystem. The 'defaults' keyword ensures standard mount behavior is applied before the 'noexec' option overrides the exec permission.

Answer

/etc/fstab: /dev/vg/lv /mnt ext4 noexec 0 0

Answer

/etc/rc.d/rc.local: mount /dev/vg/lv /mnt -o noexec

Answer

/etc/rc.local: mount -o noexec /dev/vg/lv /mnt

Question 9

A system administrator runs 'mount -a' and receives an error: 'mount: /mnt/nfs: mount point does not exist'. The /etc/fstab entry is: server:/export /mnt/nfs nfs defaults 0 0. What is the most likely cause?

Accepted Answer

The directory /mnt/nfs does not exist. The error message 'mount: /mnt/nfs: mount point does not exist' explicitly indicates that the directory /mnt/nfs is missing. The 'mount -a' command processes all entries in /etc/fstab, and for each filesystem, it requires the mount point directory to exist before the mount can succeed. Since the directory is absent, the mount fails immediately, regardless of the NFS server status or filesystem type.

Answer

The 'defaults' option does not include '_netdev'

Answer

The filesystem type should be 'nfs4'

Answer

The NFS server is unreachable

Question 10

Refer to the exhibit. An administrator runs xfs_growfs on /dev/sdc1. What is the most likely reason the command succeeded without prior partition resizing?

Accepted Answer

The underlying block device (partition or logical volume) was extended before the command. xfs_growfs can only expand an XFS filesystem to fill the available space on the underlying block device. If the command succeeded without prior partition resizing, it means the block device (e.g., a partition or logical volume) was already extended beforehand. The filesystem then uses the new space when xfs_growfs is run.

Answer

The partition was automatically resized by xfs_growfs

Answer

The filesystem was already using the full partition size and the command had no effect

Answer

The filesystem was mounted with the 'grow' option allowing online growth