Linux Advanced File System and Storage 4

Question 1

What is the default inode ratio when creating an ext4 filesystem with mkfs.ext4?

Accepted Answer

One inode per 16KB of space

Answer

By default, mkfs.ext4 creates one inode for every 16384 bytes (16KB) of filesystem space, balancing inode count against overhead.

Question 2

Which command shows I/O statistics per block device in real time?

Accepted Answer

iostat -x

Answer

iostat -x from the sysstat package reports extended I/O statistics including utilization, await time, and throughput per device.

Question 3

In Linux software RAID (mdadm), what does the '--spare-devices' option specify?

Accepted Answer

Number of hot-spare drives to add to the array

Answer

The --spare-devices option in mdadm specifies how many hot-spare drives are included in the RAID array for automatic failure recovery.

Question 4

What is the purpose of the 'barrier=0' mount option for ext4?

Accepted Answer

Disables write barriers, improving performance at the cost of data integrity on power loss

Answer

Disabling write barriers (barrier=0) improves write performance but can lead to filesystem corruption if power is lost before data is flushed.

Question 5

Which xfs_repair option performs a dry run, reporting errors without making changes?

Accepted Answer

-n

Answer

xfs_repair -n runs in no-modify mode, scanning the filesystem and reporting what would be repaired without actually making any changes.

Linux Practice Test