CHFI Storage Forensics and File System Analysis Practice Question

During a forensic examination of a Linux ext4 file system, an investigator runs the `ls -i` command and sees inode numbers. They need to examine the inode structure. Which command should they use to display detailed inode information?

⚠ Common exam trap

EC-CHFI often tests the distinction between file system analysis tools (debugfs) and general-purpose disk utilities (dd, mount, fsck), trapping candidates who confuse imaging or mounting with inode-level inspection.

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

✓

debugfs -R 'stat <inode>' /dev/sda1

The `debugfs` command is a native ext2/ext3/ext4 file system debugger that allows direct inode inspection. The `-R 'stat <inode>'` flag runs the `stat` command in debugfs to display the full inode structure, including permissions, timestamps, block pointers, and extended attributes, which is exactly what the investigator needs after seeing inode numbers from `ls -i`.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

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dd if=/dev/sda1 of=output.img
Why it's wrong here
The dd command performs a raw, bit-for-bit copy of the block device to an image file, which is essential for preserving forensic evidence but does not interpret or display any filesystem structures. Inode metadata (such as owner, permissions, timestamps, and block pointers) resides in the ext4 filesystem's inode table, which dd does not parse. To view inode details, you must open the device or its image with a filesystem-aware tool like debugfs or use stat on a mounted filesystem.
✓
debugfs -R 'stat <inode>' /dev/sda1
Why this is correct
debugfs is the standard ext2/ext3/ext4 filesystem debugger, and the -R option lets you execute a single request in non-interactive mode. The 'stat <inode>' command within debugfs prints the complete inode record, including file mode, UID/GID, size, access/change/modification times, link count, and block allocation data. This makes it the correct choice for directly querying inode information on a live device or an acquired image without mounting or modifying the filesystem.
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mount -o loop image.img /mnt
Why it's wrong here
The mount command attaches a filesystem image to the kernel's VFS namespace, making its files accessible through a mount point, but it does not output inode details itself. Even though you could later use stat or ls -i on the mounted filesystem to see inode metadata, the mount operation alone returns no such information and may also have side effects like journal replay unless explicitly mounted read-only. In forensic practice, mounting alters the system state and should be done cautiously, whereas debugfs provides a non-invasive way to inspect inodes directly.
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fsck /dev/sda1
Why it's wrong here
fsck is a filesystem consistency checking and repair utility that scans for errors in the superblock, inode table, directory entries, and other structures, potentially rewriting or repairing damaged metadata. Its primary purpose is to maintain filesystem health, not to display inode details on demand; it operates on the entire filesystem rather than querying a specific inode. Moreover, running fsck may modify the filesystem, which violates forensic integrity, making it unsuitable for examination tasks that require read-only inspection.

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CHFI Storage Forensics and File System Analysis Practice Question

Why each option matters

Option-by-option breakdown

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