EX200 Configure local storage Practice Test 4 — 15 Questions

Question 1

Which TWO commands can be used to view the current disk usage of a filesystem?

Accepted Answer

du. The `du` command (disk usage) estimates file and directory space usage, allowing you to view disk usage at the file or directory level. The `df` command (disk free) reports the amount of available and used disk space on mounted filesystems, showing overall filesystem usage. Both are standard Linux tools for examining disk consumption.

Answer

blkid

Answer

fdisk

Answer

lsblk

Question 2

Refer to the exhibit. If the system administrator wants to create a new logical volume of size 2GB in the 'rhel' volume group, what is the first command that must be executed?

Accepted Answer

pvcreate /dev/sdb1. Before a new logical volume can be created in the 'rhel' volume group, the physical volume must be prepared. The exhibit shows that /dev/sdb is not yet partitioned; the first step is to create a partition (e.g., /dev/sdb1) and then initialize it as a physical volume using `pvcreate /dev/sdb1`. Only after this can the volume group be extended and the logical volume created.

Answer

pvcreate /dev/sdb

Answer

lvcreate -L 2G -n lvdata rhel

Answer

vgextend rhel /dev/sdb

Question 3

Refer to the exhibit. A user tries to execute a script located in /data/script.sh but gets 'Permission denied'. The script has execute permissions. What is the most likely cause?

Accepted Answer

The filesystem is mounted with noexec. The most likely cause is that the filesystem where /data resides is mounted with the 'noexec' option. This mount option prevents the execution of any binary or script directly from that filesystem, regardless of the file's individual execute permissions. The 'noexec' flag is commonly set on partitions like /tmp or /var for security reasons, and it overrides the file's permission bits.

Answer

The filesystem is full

Answer

SELinux is blocking execution

Answer

The script is in a directory with noexec

Question 4

Refer to the exhibit. When the system boots, which filesystem will be mounted after the root filesystem?

Accepted Answer

/boot. According to the default boot process in RHEL 8/9, the initramfs mounts the root filesystem first, then the systemd-based init process mounts the /boot filesystem (if it is a separate partition) as specified in the /etc/fstab file. The root filesystem is mounted by the kernel or initramfs, and subsequent filesystems like /boot are mounted by systemd based on fstab entries.

Answer

None

Answer

Swap

Answer

Both /boot and swap

Question 5

An administrator adds a new 100GB disk to a RHEL 9 server. Which command should be used first to verify that the kernel has detected the new disk?

Accepted Answer

lsblk. The `lsblk` command lists all block devices detected by the kernel, including newly added disks, by reading the sysfs filesystem. It is the safest and most direct way to verify kernel detection without requiring root privileges or triggering side effects. Option D is correct because it immediately shows whether the 100GB disk appears in the device list.

Answer

udevadm trigger

Answer

dmesg | grep sd

Answer

fdisk -l

Answer

partprobe

Question 6

A system administrator needs to extend a logical volume 'lv_data' in volume group 'vg_data' by adding a new 50GB disk. Which sequence of commands should be used (assuming the filesystem is XFS)?

Accepted Answer

pvcreate, vgextend, lvextend, xfs_growfs. The proper sequence to extend an XFS logical volume is: first, initialize the new disk as a physical volume with `pvcreate`; second, add it to the volume group with `vgextend`; third, extend the logical volume with `lvextend`; and finally, grow the XFS filesystem with `xfs_growfs`. XFS does not support shrinking and requires `xfs_growfs` (not `resize2fs`) for online growth.

Answer

pvcreate, vgextend, lvextend, resize2fs

Answer

vgextend, lvcreate, pvcreate, xfs_growfs

Answer

vgextend, pvcreate, lvextend, xfs_growfs

Answer

pvcreate, lvextend, vgextend, fsck

Question 7

An administrator wants to add an additional swap partition of 2GB on device /dev/sdb1. Which set of commands should be used to enable swap and make it persistent across reboots?

Accepted Answer

mkswap /dev/sdb1; swapon /dev/sdb1; echo '/dev/sdb1 swap swap defaults 0 0' >> /etc/fstab. It follows the proper sequence to prepare and activate a swap partition on /dev/sdb1. First, `mkswap` initializes the partition as a swap area by writing a swap signature. Then `swapon` activates it immediately. Finally, adding an entry to /etc/fstab ensures the swap is automatically enabled at boot, making it persistent across reboots.

Answer

parted /dev/sdb set 1 swap on

Answer

swapadd /dev/sdb1

Answer

mkfs.ext4 /dev/sdb1; mount /dev/sdb1 /swap

Answer

None of the above

Question 8

A system administrator needs to create a point-in-time backup of a logical volume 'lv_home' that is currently mounted. Which LVM feature should be used?

Accepted Answer

lvcreate -s. The 'lvcreate -s' command creates a snapshot of a logical volume, which provides a point-in-time backup without unmounting the volume. Snapshots are a native LVM feature that allow consistent backups of mounted filesystems by capturing the state of the logical volume at the moment the snapshot is created.

Answer

lvreduce

Answer

lvchange

Answer

lvextend

Answer

pvmove

Question 9

An administrator wants to encrypt a new partition /dev/sdc1 using LUKS. Which command sequence is correct?

Accepted Answer

cryptsetup luksFormat /dev/sdc1; cryptsetup open /dev/sdc1 secret; mkfs.ext4 /dev/mapper/secret; mount /dev/mapper/secret /mnt. The proper sequence for encrypting a new partition with LUKS is: first initialize the LUKS header on the block device with `cryptsetup luksFormat`, then open the encrypted device to create a mapping under `/dev/mapper/`, then create a filesystem on the mapped device (not the raw block device), and finally mount the mapped device. This ensures the filesystem is built on top of the encrypted layer, not on the unencrypted partition.

Answer

mkfs.ext4 /dev/sdc1; cryptsetup luksFormat /dev/sdc1; cryptsetup open /dev/sdc1 secret; mount /dev/mapper/secret /mnt

Answer

cryptsetup open /dev/sdc1 secret; mkfs.ext4 /dev/mapper/secret; cryptsetup luksFormat /dev/mapper/secret; mount /dev/mapper/secret /mnt

Answer

cryptsetup luksFormat /dev/sdc1; mkfs.ext4 /dev/sdc1; cryptsetup open /dev/sdc1 secret; mount /dev/mapper/secret /mnt

Answer

cryptsetup open /dev/sdc1 secret; cryptsetup luksFormat /dev/mapper/secret; mkfs.ext4 /dev/mapper/secret; mount /dev/mapper/secret /mnt

Question 10

Which two are required to create a logical volume? (Choose two.)

Accepted Answer

Physical volume. A physical volume (PV) is required because it is the underlying storage device (e.g., a disk or partition) that LVM uses as a building block. Without a PV, there is no raw storage to allocate to a volume group. The volume group (VG) is then created from one or more PVs, and logical volumes (LVs) are carved from the VG. Both are mandatory steps in the LVM workflow.

Answer

Mount point

Answer

Filesystem

Answer

Partition

Question 11

Which two commands can be used to create a new partition on a disk without erasing existing partitions? (Choose two.)

Accepted Answer

fdisk. The `fdisk` command is a disk partitioning tool that allows you to create, delete, and modify partitions on a disk without erasing existing partitions, as long as there is unallocated space. It operates on the MBR or GPT partition table and writes changes only when explicitly saved, preserving existing partition entries.

Answer

mkswap

Answer

dd

Answer

wipefs

Question 12

Refer to the exhibit. An administrator runs lsblk and sees the above output. The administrator wants to mount /dev/sdb1 at /mnt/data. What should be done first?

Accepted Answer

Create the directory /mnt/data and then run mount. Before mounting a filesystem, the mount point directory must exist. Option A correctly instructs to create /mnt/data with mkdir -p /mnt/data and then run mount /dev/sdb1 /mnt/data. Without the directory, the mount command will fail with a 'mount point does not exist' error.

Answer

Run mount /dev/sdb1 /mnt/data

Answer

Run partprobe to detect the partition

Answer

Run mkfs.xfs /dev/sdb1

Answer

Edit /etc/fstab and add an entry

Question 13

Refer to the exhibit. An administrator needs to create a new logical volume named 'data' of size 3GB. Which command should be used?

Accepted Answer

lvcreate -n data -L 3G vg01. The `lvcreate` command with `-n data` names the logical volume 'data', `-L 3G` sets its size to 3 gigabytes, and `vg01` specifies the volume group that contains the physical volumes. This matches the requirement exactly, assuming the volume group `vg01` exists and has sufficient free extents.

Answer

lvcreate -n data -L 3G vg00

Answer

lvcreate -n data -L 3G /dev/sda1

Answer

lvcreate -n data -l 100 vg01

Answer

lvcreate -n data -l 100 vg00

Question 14

Refer to the exhibit. The /proc/mdstat output shows a RAID1 array with two devices. One of the disks (/dev/sda1) fails. Which sequence of commands would be used to remove the failed disk and add a new replacement disk /dev/sdc1?

Accepted Answer

mdadm /dev/md0 --fail /dev/sda1; mdadm /dev/md0 --remove /dev/sda1; mdadm /dev/md0 --add /dev/sdc1. It uses the proper mdadm syntax with the device name immediately after the command, followed by the action and the disk. The --fail flag marks the disk as faulty, --remove removes it from the array, and --add adds the new replacement disk. This sequence ensures the array remains in a degraded state before safely replacing the failed component.

Answer

mdadm --fail /dev/md0 /dev/sda1; mdadm --remove /dev/md0 /dev/sda1; mdadm --add /dev/md0 /dev/sdc1

Answer

mdadm /dev/md0 --set-faulty /dev/sda1; mdadm /dev/md0 --remove /dev/sda1; mdadm /dev/md0 --add /dev/sdc1

Answer

mdadm /dev/md0 --remove /dev/sda1; mdadm /dev/md0 --add /dev/sdc1

Answer

mdadm /dev/md0 --replace /dev/sda1 --with /dev/sdc1

Question 15

A Red Hat Enterprise Linux 9 server has an LVM volume group 'vg01' that contains two physical volumes: /dev/sda2 and /dev/sdb1. After a reboot, the system fails to activate the volume group. The administrator runs 'pvdisplay' and sees one physical volume as 'unknown device'. What is the most likely cause?

Accepted Answer

The LVM filter in /etc/lvm/lvm.conf is excluding /dev/sdb1. The LVM filter in /etc/lvm/lvm.conf controls which devices LVM scans during activation. If the filter excludes /dev/sdb1, LVM will not recognize that physical volume, causing the volume group to fail activation. The 'unknown device' status indicates LVM cannot access the device metadata, not that the device is missing or corrupted.

Answer

The physical volume is corrupted and needs to be restored from backup

Answer

The filesystem on the logical volume has become corrupted, preventing LVM metadata access

Answer

The UUID of the physical volume has changed due to a disk replacement