EX200 Practice Test 17 — 15 Questions

Question 1

Which command checks if a specific systemd service is currently running?

Accepted Answer

systemctl is-active. The `systemctl is-active` command is specifically designed to check whether a systemd service is currently in the 'active' (running) state. It returns an exit code of 0 if the service is active, and a non-zero exit code otherwise, making it ideal for scripting and direct status checks.

Answer

systemctl status

Answer

systemctl list-units

Answer

systemctl show

Question 2

A web server running Apache (httpd) on RHEL 9 serves content from /var/www/custom. Clients get a 403 error. The SELinux context on files is system_u:object_r:default_t:s0. Which command resolves the issue persistently without disabling SELinux?

Accepted Answer

semanage fcontext -a -t httpd_sys_content_t "/var/www/custom(/.*)?" && restorecon -R /var/www/custom. It uses `semanage fcontext` to add a persistent file context rule for `/var/www/custom` and its contents, then applies it with `restorecon`. This ensures the `httpd_sys_content_t` type is set persistently across file system relabeling, resolving the 403 error caused by the default SELinux type (`default_t`) that denies Apache access.

Answer

chcon -t httpd_sys_content_t /var/www/custom

Answer

setsebool -P httpd_enable_custom on

Answer

restorecon -R /var/www/custom

Question 3

A system administrator needs to extend an existing logical volume 'lv_data' in volume group 'vg_data'. The administrator has already added a new physical volume /dev/sdd1 to the volume group. Which sequence of commands should be used to complete the extension and ensure the filesystem is usable?

Accepted Answer

lvextend -L +10G /dev/vg_data/lv_data; resize2fs /dev/vg_data/lv_data. After adding a physical volume to the volume group, the logical volume must be extended with `lvextend`, and then the filesystem must be resized with `resize2fs` to use the new space. The filesystem remains mounted and usable throughout; no remount or filesystem recreation is needed.

Answer

lvextend -L +10G /dev/vg_data/lv_data; mount /dev/vg_data/lv_data; resize2fs /dev/vg_data/lv_data

Answer

lvextend -L +10G /dev/vg_data/lv_data; mkfs.ext4 /dev/vg_data/lv_data

Answer

lvresize -L +10G /dev/vg_data/lv_data; fsck /dev/vg_data/lv_data

Answer

vgextend vg_data /dev/sdd1; lvextend -L +10G /dev/vg_data/lv_data; resize2fs /dev/vg_data/lv_data

Question 4

Which TWO of the following are required steps when migrating a logical volume from one physical volume to another in the same volume group?

Accepted Answer

Remove the source physical volume from the volume group with vgreduce after migration. After using pvmove to relocate all physical extents from the source physical volume to the target, you must remove the source PV from the volume group using vgreduce to clean up the volume group metadata and free the device for other use. This step ensures the volume group no longer references the now-empty source PV.

Answer

Delete and recreate the logical volume on the new physical volume

Answer

Add the new physical volume to the volume group with vgextend if not already present

Answer

Extend the logical volume to include the new physical volume

Question 5

An administrator wants to optimize system performance for a database workload. Which tool should be used to select a performance profile?

Accepted Answer

tuned-adm profile throughput-performance. C is correct because `tuned-adm profile throughput-performance` selects a Tuned performance profile optimized for high throughput, which is suitable for database workloads that benefit from increased I/O and network performance. Tuned is the systemd-based dynamic system tuning daemon in RHEL that adjusts kernel parameters, disk schedulers, and other settings based on the selected profile.

Answer

performance-tune --profile database

Answer

setroubleshoot

Answer

systemctl set-profile database

Question 6

Match each command to its function in managing storage.

Accepted Answer

fdisk: Manipulate disk partition table. The correct matches are: fdisk for partition table manipulation, mkfs for filesystem creation, mount for attaching filesystems, and lvcreate for logical volume creation. Common confusions include associating df or du with filesystem creation, and confusing lvcreate with display commands.

Answer

df: Create a filesystem

Answer

lvcreate: Display disk usage

Question 7

Refer to the exhibit. The SSH service has been running for 2 weeks. An administrator wants to restart the service without interrupting existing SSH connections. Which command should they use?

Accepted Answer

systemctl reload sshd. `systemctl reload sshd` sends a SIGHUP signal to the SSH daemon, instructing it to reload its configuration file without terminating existing connections. This is the standard method for applying configuration changes to services that support graceful reloads, such as sshd, which maintains persistent sessions by only re-reading its configuration and not restarting the process.

Answer

systemctl stop sshd; systemctl start sshd

Answer

kill -HUP 1234

Answer

systemctl restart sshd

Question 8

Refer to the exhibit. Why did the sshd service fail?

Accepted Answer

The service start was requested too many times in quick succession.. B is correct because systemd's `StartLimitIntervalSec` and `StartLimitBurst` settings (default: 10 seconds and 5 starts) prevent rapid service restarts. When `sshd` fails repeatedly within the interval, systemd marks it as failed with the status 'start-limit-hit' to avoid resource exhaustion from restart loops.

Answer

The service binary is missing.

Answer

The configuration file /etc/ssh/sshd_config has a syntax error.

Answer

The system ran out of memory.

Question 9

Arrange the steps to configure a network bond (mode 1) using two interfaces (eth0, eth1) in RHEL.

Accepted Answer

Create bond interface config, then configure slave interfaces, then restart network. Network bonding requires creating a bond interface and configuring slaves, then restarting network.

Answer

Configure slave interfaces, then create bond interface config, then restart network

Answer

Restart network, then create bond interface config, then configure slave interfaces

Answer

Create bond interface config, then restart network, then configure slave interfaces

Question 10

A containerized web server needs to persist logs outside the container. Which podman run option allows the administrator to specify a bind mount with mount propagation options?

Accepted Answer

--mount. The `--mount` flag in `podman run` provides the most granular control over bind mounts, including the ability to specify mount propagation options (e.g., `shared`, `slave`, `private`) via the `propagation` parameter. This is essential for persisting container logs to the host filesystem while controlling how mount events are propagated between the container and the host.

Answer

--volume

Answer

--bind

Answer

-v

Question 11

An administrator needs to ensure that the httpd service starts automatically after a system reboot and is set to start immediately without rebooting. Which command should be used?

Accepted Answer

systemctl enable --now httpd. `systemctl enable --now httpd` both creates the necessary symlinks to start the httpd service automatically at boot (enable) and starts the service immediately (--now) without requiring a reboot. This combines two operations into one command, satisfying both requirements in the question.

Answer

systemctl set-default httpd

Answer

systemctl add httpd

Answer

systemctl start --enable httpd

Question 12

An administrator needs to monitor network traffic on a specific interface in real time. Which tool is most appropriate for this task?

Accepted Answer

tcpdump -i eth0. tcpdump -i eth0 captures and displays packet headers in real time on the specified interface (eth0). It uses libpcap to intercept raw network frames at the data link layer, making it the standard tool for live traffic monitoring and analysis.

Answer

ip -s link

Answer

ss -tulpn

Answer

nload eth0

Question 13

Put the steps to configure NFS server to export /nfsshare to a specific client in order.

Accepted Answer

Step 1: Create the /nfsshare directory. Step 2: Edit /etc/exports to add the export entry. Step 3: Run exportfs -a to export the directory. Step 4: Start and enable the NFS server service.. NFS export configuration involves creating the directory, editing /etc/exports, exporting, and starting services.

Answer

Step 1: Edit /etc/exports to add the export entry. Step 2: Create the /nfsshare directory. Step 3: Start and enable the NFS server service. Step 4: Run exportfs -a.

Answer

Step 1: Start and enable the NFS server service. Step 2: Create the /nfsshare directory. Step 3: Edit /etc/exports to add the export entry. Step 4: Run exportfs -a.

Answer

Step 1: Create the /nfsshare directory. Step 2: Run exportfs -a. Step 3: Edit /etc/exports to add the export entry. Step 4: Start and enable the NFS server service.

Question 14

A logical volume /dev/vg_data/lv_data formatted as XFS is full. The administrator extends the LV by 1 GB using 'lvextend -L +1G /dev/vg_data/lv_data'. Which additional command is required to use the new space?

Accepted Answer

xfs_growfs /mount/point. After extending the logical volume, the XFS file system must be grown to recognize the new space. The `xfs_growfs` command resizes an XFS file system to fill the available space in the underlying block device, and it requires the mount point as an argument (not the device). This is necessary because XFS does not support online resizing via a simple block device extension; the file system must be explicitly told to expand.

Answer

xfs_repair /dev/vg_data/lv_data

Answer

resize2fs /mount/point

Answer

lvresize -L +1G /dev/vg_data/lv_data

Question 15

Refer to the exhibit. A security analyst reviews the journal output for sshd.service. Which of the following best describes the observed pattern of events?

Accepted Answer

The system experienced a brute-force attack on the root account originating from IP 192.168.1.100, which eventually succeeded.. The journal output shows repeated failed authentication attempts for the root user from IP 192.168.1.100, followed by a successful login. This pattern is characteristic of a brute-force attack where an attacker tries many passwords until one works. The final 'Accepted password for root' line confirms the attack succeeded, making D correct.

Answer

The system is under a denial-of-service attack because the connections are being closed before authentication.

Answer

The SSH service is malfunctioning and dropping connections due to a configuration error.

Answer

Multiple hosts are attempting to connect to the SSH service simultaneously, causing connection errors.