EX200 Create and configure file systems Practice Question
Which TWO commands can mount an ISO file /tmp/rhel.iso to /mnt/iso?
⚠ Common exam trap
Candidates often think `mount` can directly handle a file without the loop option (Option E), or they may confuse `losetup` syntax (Option D) with the correct procedure, leading to errors in a real exam scenario.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
mount -o loop /tmp/rhel.iso /mnt/iso
Option A is correct because `mount -o loop /tmp/rhel.iso /mnt/iso` uses the loop option to associate the ISO file with a loop device and mount it; on modern Linux, mount auto-detects the ISO9660 filesystem, so no explicit type is required. Option C is also correct because `mount -t iso9660 -o loop /tmp/rhel.iso /mnt/iso` explicitly specifies the ISO9660 filesystem type while still using the loop option, which is the traditional and fully explicit way to mount an ISO image. Option B is wrong because `isomount` is not a standard Linux command. Option D is wrong as written because `losetup /tmp/rhel.iso` without `-f` does not reliably create/attach a loop device and the chained mount assumes /dev/loop0, which may not be the device assigned. Option E is wrong because `mount /tmp/rhel.iso /mnt/iso` lacks the loop option and will fail to mount a regular file as a block device.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
mount -o loop /tmp/rhel.iso /mnt/iso
Why this is correct
The -o loop option is what makes this command correct. Without an explicit filesystem type, mount probes the file and detects the ISO 9660 filesystem automatically. The kernel associates the regular file /tmp/rhel.iso with an available loop device (e.g., /dev/loop0), then mounts that device at /mnt/iso. This is the standard, minimal way to mount an ISO file.
- ✗
isomount /tmp/rhel.iso /mnt/iso
Why it's wrong here
There is no standard Linux command named isomount in util-linux, coreutils, or common distribution packages. This command would simply fail with 'command not found'. The correct approach is to use mount with the -o loop option, which transparently handles the loop device creation and filesystem mounting in one step.
- ✓
mount -t iso9660 -o loop /tmp/rhel.iso /mnt/iso
Why this is correct
This is correct because -t iso9660 explicitly identifies the filesystem type for the ISO file, and -o loop still tells mount to set up a loop device. While auto-detection often works, specifying -t can be useful when probe heuristics might fail or when you want to clearly document the filesystem type. It is a valid, if slightly more verbose, alternative to the minimal form.
- ✗
losetup /tmp/rhel.iso && mount /dev/loop0 /mnt/iso
Why it's wrong here
This fails for two independent reasons. First, losetup requires a loop device argument; the syntax losetup /tmp/rhel.iso is invalid and will return an error because no device is specified. Second, even if you wrote losetup -f /tmp/rhel.iso to automatically allocate a loop device, that device is not guaranteed to be /dev/loop0—it could be loop1 or a higher number—so the subsequent mount would likely target the wrong device.
- ✗
mount /tmp/rhel.iso /mnt/iso
Why it's wrong here
Without -o loop, mount treats its first argument as a block device node (like /dev/sr0) and does not create a loop device for a regular file. Since /tmp/rhel.iso is a regular file, mount will fail with an error such as 'failed to setup loop device' or 'not a block device'. The -o loop flag is essential to tell mount to use the loop mechanism.
Go deeper
Related to this question
About these practice questions
Courseiva writes every EX200 question from scratch — 427 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This EX200 practice question is part of Courseiva's free Red Hat certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the EX200 exam.