Advanced File System and Storage Flashcards

What does the 'dumpe2fs' command do?

Answer: Dumps ext2/3/4 filesystem superblock and block group information

dumpe2fs prints the superblock and block group descriptor table information for an ext2/3/4 filesystem.

Which NFS mount option ensures that all file operations on the client are completed before returning to the application?

Answer: sync

The sync mount option forces synchronous I/O so all writes are committed to the server before the client returns control to the application.

What is the role of the journal in an ext3/ext4 filesystem?

Answer: Records metadata changes before they are committed, ensuring consistency after a crash

The journal (write-ahead log) records pending metadata or data changes so the filesystem can replay or discard them after an unclean shutdown.

Which command permanently removes an LVM Logical Volume?

Answer: lvremove

lvremove deactivates and permanently deletes a Logical Volume and all its data from the Volume Group.

What is the effect of mounting a filesystem with the 'ro' option?

Answer: Mounts the filesystem in read-only mode, preventing any writes

The ro mount option causes the kernel to mount the filesystem read-only, so no modifications can be made to files or directories.

Which tool is used to benchmark raw disk throughput on a Linux block device?

Answer: hdparm -tT /dev/sda

hdparm -tT performs buffered and cached read benchmarks on a block device, providing a quick indication of raw disk and cache throughput.

What happens when a Btrfs filesystem runs out of metadata space even though data space is available?

Answer: The filesystem becomes read-only and returns ENOSPC errors

When Btrfs exhausts its metadata allocation, the filesystem is remounted read-only to prevent corruption, even if raw storage remains for data.