101.1 Determine and configure hardware settings

Question 1

What is a file system?

Answer 1

A file system is a method of laying off files and folders on a physical hard disk.

Question 2

What creates a pseudo file system in the system?

Answer 2

A pseudo file system does not exist on a physical hard disk. It is created by the Linux Kernel.

Question 3

When is a pseudo file system created?

Answer 3

It is created by the Linux Kernel after the computer boots.

Question 4

Every process that runs on the system is associated with what?

Answer 4

Every process that runs on the system is associated with a PID (process ID)

Question 5

What happens to a pseudo file system when the computer is rebooted?

Answer 5

It is wiped out while the computer is being turned off and then recreated once again when it boots up.

Question 6

What type of information can be found in the pseudo file system called /sys?

Answer 6

/sys contains info about the hardware currently connected to the computer

Question 7

In which pseudo file system can you find information related to the hardware and kernel info?

Answer 7

/sys

Question 8

What can you see inside /proc ?

Answer 8

Within the /proc directory, you can see:

• all processes that are running on the system
• their specific directory
• their process ID.

Question 9

What type of kernel is the Linux Kernel?

Answer 9

The Linux kernel is a monolithic kernel.

Question 10

What is the purpose of the Linux Kernel?

Answer 10

It provides a way for the resources of the system (CPU, RAM, networking capabilities, etc) to operate with the hardware that’s connected to it.

Question 11

What does “monolithic kernel” mean?

Answer 11

It means that the kernel handles all memory management and hardware devices interactions.
It also means that extra functionality can be added dynamically through kernel modules.

Question 12

What does “loading kernel modules dynamically” mean?

Answer 12

It means the monolithic kernel can load kernel modules without rebooting the system.

Question 13

In what form do kernel modules come a lot of the time?

Answer 13

They may come in the form of third party device drivers.

Question 14

Which is the basic command we can use to gather info about the kernel we are currently running?

Answer 14

uname

Question 15

What output does #uname -m give us?

Answer 15

uname -m gives the machine architecture, such as x86_64 (64bit kernel)

Question 16

Which command will display a listing of all currently loaded kernel modules?

Answer 16

lsmod

Question 17

What command gives you information about a specific kernel module?

Answer 17

modinfo

Question 18

Which command do you use to unload a kernel module?

Answer 18

modprobe -r

Question 19

Which command do you use to load a kernel module?

Answer 19

modprobe >kernel module name>

Question 20

Which flag of the uname command will give us the most info about the kernel?

Answer 20

uname -a

Question 21

What is the d-bus service?

Answer 21

It is the data bus service. It passes all information about everything that goes on within the system to other services and devices.

Question 22

What does udev do when a piece of hardware is connected to a computer?

Answer 22

The udev service detects the piece of hardware that has been connected and passes this information to the D Bus service.

Question 23

Where does hardware picked up by the udev service get added to?

Answer 23

It gets added to /dev

Question 24

What does /dev contain?

Answer 24

It contains information on all of the connected hardware on a system.

Question 25

What is the udev service?

Answer 25

It is the Linux device manager for the kernel. It links info on system hardware to /dev

Question 26

What does the lspci command display?

Answer 26

it displays info about PCI devices attached to a computer.

Question 27

Which command do you use to list the information on USB devices attached to a computer?

Answer 27

lsusb

Question 28

What command displays information on processors on a system?

Answer 28

lscpu

Question 29

What info can you find in the #lscpu command?

Answer 29

The architecture of the processor, the vendor, the model name, its speed.

Question 30

Which command would you use to see what hard disks are attached to the system?

Answer 30

lsblk

Question 31

What command will list out which components of the hardware are being used with which particular kernel module?

Answer 31

lspci -k

Question 32

Give examples of PCI (Peripheral Component Interconnect) devices

Answer 32

A PCI device is any piece of computer hardware that plugs directly into a PCI slot on a computer’s motherboard.
Example: Network, sound, video cards, wireless adapter.

Question 33

What directory does the lspci command query to get information about the PCI devices?

Answer 33

The /dev directory

Question 34

What is the Kernel Ring Buffer?

Answer 34

Area of RAM where the Kernel writes all of its system messages to.