EX200 Create and configure file systems Practice Test 3 — 15 Questions

Question 1

A company policy requires that all new logical volumes be created with a physical extent size of 16 MiB to optimize performance for large sequential I/O. During the creation of a new volume group, what parameter should be used?

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

Accepted Answer

vgcreate -s 16M vg_data /dev/sdc1. The `-s` parameter in `vgcreate` sets the physical extent (PE) size for the volume group. A PE size of 16 MiB is specified with `-s 16M`, which ensures all subsequent logical volumes in that VG use 16 MiB extents, optimizing performance for large sequential I/O by reducing metadata overhead.

Answer

vgcreate -p 16M vg_data /dev/sdc1

Answer

vgcreate -L 16M vg_data /dev/sdc1

Answer

vgcreate -e 16M vg_data /dev/sdc1

Answer

vgcreate -c 16M vg_data /dev/sdc1

Question 2

An administrator is configuring an NFS mount in /etc/fstab to mount from server:/export to /mnt/data. The mount must use the 'hard' and 'nosuid' options. Which line is correct?

Accepted Answer

server:/export /mnt/data nfs nosuid,hard 0 0. It specifies the NFS filesystem type and includes both required mount options: 'nosuid' (disallows set-user-identifier/set-group-identifier bits) and 'hard' (retries NFS requests indefinitely until the server responds). The syntax follows the correct /etc/fstab format: :/ .

Answer

server:/export /mnt/data nfs defaults,noexec,nodev 0 0

Answer

server:/export /mnt/data nfs nosuid,hard,defaults 0 0

Answer

server:/export /mnt/data ext4 defaults 0 0

Answer

server:/export /mnt/data nfs suid,soft 0 0

Question 3

Which command can be used to display a list of all currently mounted filesystems on a Linux system?

Accepted Answer

mount. The `mount` command with no arguments displays a list of all currently mounted filesystems, showing the device, mount point, filesystem type, and mount options. This is the standard and most direct way to view active mounts on a Linux system.

Answer

fdisk -l

Answer

lsblk -m

Answer

cat /proc/filesystems

Answer

df -a

Question 4

A system has two logical volumes in the same volume group: 'lv_prod' (100% used) and 'lv_backup' (20% used). The administrator wants to allocate 5 GiB from 'lv_backup' to 'lv_prod' without unmounting any filesystems. Is this possible and why?

Accepted Answer

No, because ext4 filesystems cannot be shrunk online; they must be unmounted.. Ext4 filesystems do not support online shrinking; they must be unmounted before reducing the logical volume. Since the administrator wants to shrink lv_backup (which is only 20% used) to free 5 GiB, the ext4 filesystem on that LV must be unmounted first. Without unmounting, the lvreduce operation would fail, making the scenario impossible as described.

Answer

Yes, use lvreduce and lvextend while mounted; ext4 supports online shrinking.

Answer

No, because LVM does not allow freeing extents from an LV while it is active.

Answer

Yes, use lvresize to move extents between LVs directly.

Question 5

Which TWO of the following commands can be used to create an XFS filesystem on a block device?

Accepted Answer

mkfs.xfs /dev/sdb1. The `mkfs.xfs` command (option B) directly creates an XFS filesystem on a block device. The `mkfs -t xfs` command (option E) is the generic front-end that calls the same XFS-specific tool, making both valid. These are the standard methods for formatting a partition with the XFS filesystem in Red Hat Enterprise Linux.

Answer

mkfs.ext4 /dev/sdb1

Answer

xfs_admin /dev/sdb1

Answer

mke2fs /dev/sdb1

Question 6

Which TWO LVM commands can be used to reduce the size of a logical volume?

Accepted Answer

lvresize. Both `lvresize` and `lvreduce` can reduce the size of a logical volume. `lvresize` is the general-purpose command for resizing LVs, and when used with the `-L` or `--size` option to specify a smaller size, it shrinks the volume. `lvreduce` is a dedicated command that specifically reduces the size of a logical volume, offering the same functionality as `lvresize --size` but with a more explicit name. Both commands require the filesystem to be shrunk first (if it contains data) using tools like `resize2fs` or `xfs_growfs` (though XFS cannot be shrunk).

Answer

lvchange

Answer

lvdisplay

Answer

lvextend

Question 7

Which THREE of the following mount options are commonly used to enhance security on a filesystem?

Accepted Answer

nosuid. The `nosuid` option prevents the set-user-identifier (setuid) and set-group-identifier (setgid) bits from taking effect on the filesystem. This blocks unprivileged users from executing binaries with elevated privileges, a common vector for privilege escalation attacks.

Answer

suid

Answer

defaults

Question 8

Based on the exhibit, which mount point is mounted with the 'noexec' option?

Accepted Answer

/tmp. The /tmp mount point is configured with the 'noexec' option, as shown in the exhibit (e.g., in /etc/fstab or the output of mount or findmnt). This prevents execution of binaries directly from the /tmp filesystem, which is a common security hardening practice to mitigate the risk of attackers running malicious scripts or binaries from a world-writable directory.

Answer

/data

Answer

/

Answer

/var

Answer

/boot

Question 9

Based on the exhibit, how much free space is available in the volume group vg00?

Accepted Answer

19.98 GiB. The VG free space is calculated from the total number of Physical Extents (PEs) and the PE size. The output shows 5115 PEs and a PE size of 4.00 MiB, so total free space = 5115 × 4 MiB = 20460 MiB = 19.98 GiB (since 20460 ÷ 1024 = 19.98046875). No Logical Volumes are allocated, so all PEs are free. Option B (10235 MiB) is exactly half of 20470 MiB, a common miscalculation. Option C (20.00 GiB) is the raw PV size, ignoring the PE overhead. Option D (19.99 GiB) is a rounding error. Option E (5115 MiB) confuses the PE count with the free space in MiB.

Answer

10235 MiB

Answer

20.00 GiB

Answer

19.99 GiB

Answer

5115 MiB

Question 10

Based on the exhibit, which device is used for swap?

Accepted Answer

The UUID deadbeef-cafe-babe-0000-000000000000. The exhibit shows a swap partition with the UUID deadbeef-cafe-babe-0000-000000000000. In Red Hat Enterprise Linux, swap devices are identified by their UUID in /etc/fstab, and the 'sw' or 'swap' keyword in the mount options column confirms this. The other UUIDs correspond to non-swap filesystems or are not present in the exhibit.

Answer

/dev/mapper/vg00-home

Answer

/dev/sda2

Answer

The UUID abcdef01-2345-6789-abcd-ef0123456789

Answer

The UUID 12345678-1234-1234-1234-123456789abc

Question 11

A system administrator needs to create a file system on a new 10GB partition /dev/sdb1 for use with a database that requires high reliability and supports snapshots. Which file system type should be chosen?

Accepted Answer

xfs. XFS is the correct choice because it is a high-performance, 64-bit journaling file system that supports snapshots via LVM or external tools, and is designed for large files and partitions. For a database requiring high reliability and snapshot capabilities, XFS provides robust data integrity features and is the default file system in Red Hat Enterprise Linux 8 and later, making it the recommended option for this scenario.

Answer

ext4

Answer

vfat

Answer

btrfs

Question 12

A technician runs 'mkfs.xfs /dev/sdb1' and later mounts it. The file system is reported as having a block size of 1024 bytes. What is the most likely reason?

Accepted Answer

The partition size is less than 1GB, so mkfs.xfs automatically used a 1024-byte block size.. Mkfs.xfs automatically selects a 1024-byte block size when the underlying partition is smaller than 1 GB. This is a built-in heuristic in the XFS filesystem to optimize metadata overhead and space utilization on small volumes. The technician did not specify a block size, so the tool applied this default behavior based on partition size.

Answer

The administrator used the -b size=1024 option.

Answer

The block size setting was ignored due to a kernel limitation.

Answer

The default block size for XFS is 1024 bytes.

Question 13

A server running RHEL 9 has an LVM logical volume /dev/vg00/lvol0 formatted with XFS, mounted at /data. The administrator needs to increase the file system size from 100GB to 150GB. Which command sequence should be used?

Accepted Answer

lvextend -L +50G /dev/vg00/lvol0; xfs_growfs /data. It first extends the logical volume by the exact amount needed (+50G) using lvextend, then grows the XFS filesystem to match using xfs_growfs. XFS filesystems can be grown online (no unmount required), and xfs_growfs expands the filesystem to fill the available space in the logical volume.

Answer

xfs_info /data; lvextend -L 150G /dev/vg00/lvol0

Answer

umount /data; lvextend -L +50G /dev/vg00/lvol0; mount /data; xfs_growfs /data

Answer

resize2fs /dev/vg00/lvol0

Question 14

Which command displays the UUID of all file systems on the system?

Accepted Answer

blkid. The `blkid` command is the correct choice because it is specifically designed to locate and display block device attributes, including the UUID, filesystem type, and label, for all filesystems on the system. It reads data from the `/dev/disk/by-uuid/` directory and the `udev` database, making it the most direct and reliable tool for querying UUIDs without requiring root privileges for basic output.

Answer

dumpe2fs -h

Answer

lsblk

Answer

fdisk -l

Question 15

An administrator wants to ensure that a file system is automatically mounted at boot. Which file should be edited?

Accepted Answer

/etc/fstab. The /etc/fstab file is the standard configuration file that defines how disk partitions, block devices, and remote filesystems should be mounted into the filesystem tree, including options for automatic mounting at boot time. The system reads this file during the boot process (via systemd or the traditional mount -a command) to mount all filesystems listed with the 'auto' or nofail option.

Answer

/etc/rc.local

Answer

/boot/grub2/grub.cfg

Answer

/etc/mtab