Chapter 13 File Systems

Question 2

What is a block device in Linux?

Answer 2

A storage device that must be formatted before the file system can use it

Common examples include hard drives, which are stored in ‘/dev’.

Question 3

What are the common devices in Linux storage?

Answer 3

• SATA hard drives
• First hard drive: sda
• First partition: sda1
• Second partition: sda2
• Second hard disk: sdb

Devices are identified in the ‘/dev’ directory.

Question 4

What must be done to a partition before it can be used?

Answer 4

It must be mounted at a mount point

The first partition loaded upon boot is the root partition.

Question 5

What is a logical volume in Linux?

Answer 5

A collection of block devices that appears as one partition

It is created from multiple block devices and is also viewable in ‘/dev’.

Question 6

Which command is used to view information about partitions/volumes?

Answer 6

$df

Use ‘$df -h’ for human-readable sizes.

Question 7

What command is used to mount a device in Linux?

Answer 7

mount

You can specify the device name or the UUID.

Question 8

How do you manually mount the second partition on the first disk to /backup?

Answer 8

$sudo mount /dev/sda2 /backup

If the device is disconnected, it will unmount automatically.

Question 9

What should you do before disconnecting a device?

Answer 9

Unmount the device

Use ‘$sudo unmount /backup’ to safely disconnect.

Question 10

What command can be used to find which files are open on a mounted device?

Answer 10

$sudo lsof /backup

This command lists open files and their process IDs.

Question 11

What is the purpose of the mlocate service?

Answer 11

Creates a database of files and paths every day

The command ‘locate’ searches this database.

Question 12

What command is used to locate files in Linux?

Answer 12

locate

Use ‘$locate homework’ to find files containing ‘homework’.

Question 13

What command is used for a real-time search of files?

Answer 13

find

It is slower but more accurate for frequently changing systems.

Question 14

How do you find files owned by the user hector?

Answer 14

$find / -user hector

This command searches the entire file system.

Question 15

What command would you use to find files larger than 5GB?

Answer 15

$find / -size +5G

This command searches the entire file system for large files.

Question 16

To find files modified less than an hour ago, you would use:

Answer 16

$find / -mmin 60

This command searches for recently modified files.