Linux Professional Institute Certification Level 2 LPIC-2 practice test

Which TWO of the following are valid methods to modify kernel parameters at runtime without rebooting?

Trap 1: Using modprobe to load kernel modules with parameters

modprobe loads modules, not modifies existing parameters.

Trap 2: Editing /etc/sysctl.conf and running sysctl --system

This applies settings from files, but it's not a direct runtime modification.

Trap 3: Adding parameters to the kernel command line in /etc/default/grub

This requires a reboot to take effect.

A
Using modprobe to load kernel modules with parameters
Why wrong: modprobe loads modules, not modifies existing parameters.
B
Editing /etc/sysctl.conf and running sysctl --system
Why wrong: This applies settings from files, but it's not a direct runtime modification.
C
Writing to files in /proc/sys/ using echo
Writing directly to /proc/sys/ files changes parameters immediately.
D
Using the sysctl command to set parameters
sysctl modifies parameters in /proc/sys/ immediately.
E
Adding parameters to the kernel command line in /etc/default/grub
Why wrong: This requires a reboot to take effect.

Question 2hardmultiple choice

A systems administrator is troubleshooting a server that fails to boot after a kernel upgrade. The boot process hangs at the stage where the kernel attempts to mount the root filesystem. Which of the following is the most likely cause?

Trap 1: The root filesystem is formatted with an unsupported filesystem…

This would typically produce an error message, not a hang.

Trap 2: The initrd image is missing from the /boot partition.

An initrd is not always required; the kernel can mount root directly.

Trap 3: The GRUB bootloader is not installed on the MBR.

This would prevent the bootloader from loading entirely, not cause a hang at root mount.

A
The root= parameter in the kernel command line points to a non-existent device.
A missing root device causes the kernel to hang while waiting for the device to appear.
B
The root filesystem is formatted with an unsupported filesystem type.
Why wrong: This would typically produce an error message, not a hang.
C
The initrd image is missing from the /boot partition.
Why wrong: An initrd is not always required; the kernel can mount root directly.
D
The GRUB bootloader is not installed on the MBR.
Why wrong: This would prevent the bootloader from loading entirely, not cause a hang at root mount.

Question 3hardmultiple choice

An administrator is designing a high-availability storage solution using DRBD. The requirement is to have two nodes with synchronous replication and automatic failover in case of primary node failure. Which configuration best achieves this?

Trap 1: Export the DRBD block device via NFS and use a load balancer.

NFS adds a single point of failure and complexity.

Trap 2: Primary/Secondary DRBD resource with manual failover using drbdadm.

Manual failover does not meet the automatic failover requirement.

Trap 3: DRBD with Heartbeat to automatically promote the secondary on…

This provides automatic failover but only one active node, not optimal for HA.

A
Export the DRBD block device via NFS and use a load balancer.
Why wrong: NFS adds a single point of failure and complexity.
B
Primary/Secondary DRBD resource with manual failover using drbdadm.
Why wrong: Manual failover does not meet the automatic failover requirement.
C
DRBD with Heartbeat to automatically promote the secondary on primary failure.
Why wrong: This provides automatic failover but only one active node, not optimal for HA.
D
DRBD in Primary/Primary mode managed by Pacemaker cluster stack.
Allows both nodes active and automatic failover via Pacemaker.

Question 4mediummultiple choice

Refer to the exhibit. The system boots successfully, but the root filesystem is mounted as read-only even after the boot process completes. Which of the following is the most likely cause?

Exhibit

Refer to the exhibit.

[    0.000000] Linux version 5.10.0-8-amd64 (debian@amd64) #1 SMP Debian 5.10.46-4 (2021-08-03)
[    0.000000] Command line: BOOT_IMAGE=/vmlinuz-5.10.0-8-amd64 root=/dev/mapper/vg-root ro quiet
[    0.000000] Memory: 1024M/2048M available (8192K kernel code, 1024K rwdata, 2048K rodata, 512K init, 256K bss, 1024K reserved)
[    0.000000] Kernel command line: BOOT_IMAGE=/vmlinuz-5.10.0-8-amd64 root=/dev/mapper/vg-root ro quiet
[    1.234567] device-mapper: ioctl: 4.43.0-ioctl (2021-02-07) initialised: dm-devel@redhat.com
[    2.345678] EXT4-fs (dm-0): mounted filesystem with ordered data mode. Opts: (null)
[    3.456789] systemd[1]: systemd 247 running in system mode. (+PAM +AUDIT +SELINUX +IMA +APPARMOR +SMACK +SYSVINIT +UTMP +LIBCRYPTSETUP +GCRYPT +GNUTLS +ACL +XZ +LZ4 +ZSTD +SECCOMP +BLKID +ELFUTILS +KMOD -IDN2 +IDN -PCRE2 default-hierarchy=hybrid)

Trap 1: The root device /dev/mapper/vg-root does not exist.

The boot log shows the filesystem was mounted successfully, so the device exists.

Trap 2: The root filesystem is damaged and forces read-only mount.

No filesystem errors are shown in the log; EXT4 mounted cleanly.

Trap 3: SELinux is enforcing and prevents write access to the root…

SELinux does not enforce read-only mount; it controls access to files.

A
The kernel command line contains the 'ro' parameter, which remains in effect.
The 'ro' parameter causes the root filesystem to be mounted read-only unless remounted rw by init.
B
The root device /dev/mapper/vg-root does not exist.
Why wrong: The boot log shows the filesystem was mounted successfully, so the device exists.
C
The root filesystem is damaged and forces read-only mount.
Why wrong: No filesystem errors are shown in the log; EXT4 mounted cleanly.
D
SELinux is enforcing and prevents write access to the root filesystem.
Why wrong: SELinux does not enforce read-only mount; it controls access to files.

Question 5mediummulti select

Which TWO statements about LVM thin provisioning are correct?

Trap 1: Thin pools are created using the 'pvcreate' command.

Thin pools are created with lvcreate --type thin-pool.

Trap 2: Thin provisioning requires a dm-cache device to function.

dm-cache is a separate feature for caching.

Trap 3: Thin volumes automatically grow when they run out of space.

Auto-extension requires monitoring and manual intervention.

A
Thin pools are created using the 'pvcreate' command.
Why wrong: Thin pools are created with lvcreate --type thin-pool.
B
The filesystem on a thin volume must support the 'discard' option to free unused space.
fstrim or mount -o discard allows space reclamation.
C
Thin volumes can be over-provisioned, allowing more virtual space than physical storage.
Over-provisioning is a key feature of thin provisioning.
D
Thin provisioning requires a dm-cache device to function.
Why wrong: dm-cache is a separate feature for caching.
E
Thin volumes automatically grow when they run out of space.
Why wrong: Auto-extension requires monitoring and manual intervention.

Review the full routing breakdown →

Question 6hardmultiple choice

A client on the internet sends a TCP SYN packet to 10.0.1.10:8080. The router receives it on eth0. According to the exhibit, what will happen to the packet?

Network Topology

Trap 1: The packet is dropped because the destination IP is not directly…

DNAT changes the destination to a directly connected network (10.0.2.0/24).

Trap 2: The packet is forwarded to 10.0.1.1 because it is the default…

After DNAT, the destination is 10.0.2.5, so routing will send it to that network, not the default gateway.

Trap 3: The packet is forwarded to 10.0.2.5:80 via eth1, with source IP…

MASQUERADE would only change source if the packet originated from 10.0.2.0/24.

A
The packet is dropped because the destination IP is not directly connected.
Why wrong: DNAT changes the destination to a directly connected network (10.0.2.0/24).
B
The packet is forwarded to 10.0.1.1 because it is the default gateway.
Why wrong: After DNAT, the destination is 10.0.2.5, so routing will send it to that network, not the default gateway.
C
The packet is forwarded to 10.0.2.5:80 via eth1, with source IP changed to 10.0.2.20.
Why wrong: MASQUERADE would only change source if the packet originated from 10.0.2.0/24.
D
The packet is forwarded to 10.0.2.5:80 via eth1, with source IP unchanged.
As described, DNAT changes destination, routing sends it to eth1, and no SNAT is applied.