EX200 Configure local storage Practice Test 3 — 15 Questions

Question 1

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 2

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 3

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 4

After editing /etc/fstab to add a mount for /data, the system fails to boot and drops to a maintenance shell. Which recovery step should be taken first?

Accepted Answer

Boot into rescue mode and comment out or correct the problematic line in /etc/fstab. When a misconfigured /etc/fstab entry prevents the system from booting, the first recovery step is to boot into rescue mode (or single-user mode if available) and edit /etc/fstab to comment out or correct the problematic line. This restores the ability to boot normally without reinstalling or removing hardware.

Answer

Remove the disk that contains the problematic mount

Answer

Boot into single-user mode and run 'mount -a' to list errors

Answer

Boot from installation media and reinstall the operating system

Answer

At the maintenance shell, run 'systemctl emergency' to drop to emergency mode

Question 5

A database server requires a filesystem that supports very large files (over 2TB) and online defragmentation. Which filesystem type should be used?

Accepted Answer

xfs. XFS is the correct choice because it supports filesystem sizes up to 8 exabytes and individual file sizes up to 8 exabytes, easily exceeding the 2TB requirement. It also supports online defragmentation via the `xfs_fsr` command, allowing defragmentation while the filesystem is mounted and in use.

Answer

ext4

Answer

vfat

Answer

swap

Answer

btrfs

Question 6

An administrator is configuring a RAID 1 (mirror) using two 100GB disks /dev/sda and /dev/sdb. After creating the array, which command(s) will verify the array status? (Choose the best answer.)

Accepted Answer

mdadm --detail /dev/md0. To verify the status of a RAID 1 array, the most appropriate command is `mdadm --detail /dev/md0`, which displays the current state, sync status, and member disks. While `cat /proc/mdstat` can also show the status, `mdadm --examine` is used to inspect the superblock on a component disk and does not directly report whether the array is active, degraded, or synchronizing. Therefore, requiring both A and B is unnecessary and fails to include the standard verification alternatives.

Answer

mdadm --examine /dev/sda

Answer

cat /proc/mdstat

Answer

mdadm --query /dev/md0

Answer

Both A and B

Question 7

To ensure that a filesystem is mounted automatically at boot and that only root can write to it, which mount options should be used in /etc/fstab? (Assume the filesystem permissions are appropriately set.)

Accepted Answer

defaults. The 'defaults' mount option in /etc/fstab includes 'auto' for automatic mounting at boot, 'rw' for read-write access, and 'nouser' which restricts mounting to root only. However, the requirement that only root can write to the filesystem is satisfied by the filesystem permissions being appropriately set (as stated in the question). The 'defaults' option does not include any explicit write restriction; it is the permissions on the mount point that enforce root-only write. Thus, 'defaults' is sufficient because it provides the necessary automatic mounting and allows root write access while relying on the pre-set permissions for write restriction.

Answer

ro,noauto

Answer

noexec,nodev,nosuid

Answer

rw,suid,dev,exec

Answer

auto,root

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

A system administrator adds a new 10GB disk (/dev/sdb) to a server. The requirement is to create a single ext4 filesystem on the entire disk for storing application data. Which sequence of commands should be used?

Accepted Answer

fdisk /dev/sdb (create one partition) -> mkfs.ext4 /dev/sdb1 -> mount /dev/sdb1 /data. The correct RHCSA procedure is to create a partition (e.g., /dev/sdb1) using fdisk, format it with mkfs.ext4, and mount it. While it is technically possible to place an ext4 filesystem directly on /dev/sdb without partitioning, the exam expects you to create a partition first. The explanation incorrectly states that the system will not recognize a filesystem on a whole disk, which is not true.

Answer

fdisk /dev/sdb (create one partition) -> mkfs.ext4 /dev/sdb (without partition number)

Answer

mkfs.ext4 /dev/sdb && mount /dev/sdb /data

Answer

mkfs.ext4 /dev/sdb && mount /dev/sdb /data

Question 15

Which TWO of the following are valid reasons to use LVM in a Red Hat Enterprise Linux environment?

Accepted Answer

Ability to resize logical volumes without repartitioning. LVM allows you to resize logical volumes (LVs) online or offline without needing to repartition the underlying disk, which is a key advantage over traditional partitions. Option C is correct because LVM provides snapshot functionality, which creates a point-in-time copy of a logical volume for consistent backups or testing, without requiring additional backup software.

Answer

Improved disk I/O performance over direct partitions

Answer

Simplification of disk partitioning by removing the need for partitions

Answer

Ability to create RAID arrays without mdadm