Hypervisors

Question 1

What is the main purpose of hypervisors on Linux?

Answer 1

To enable virtualization and allow creation and management of virtual machines on Linux systems.

Question 2

What is KVM in the context of Linux virtualization?

Answer 2

KVM (Kernel-based Virtual Machine) is a built-in feature of the Linux kernel that allows Linux to act as a Type 1 hypervisor, providing CPU and memory virtualization.

Question 3

Is KVM integrated into the Linux kernel or a separate application?

Answer 3

KVM is integrated directly into the Linux kernel for high efficiency.

Question 4

Does KVM create or manage virtual machines by itself?

Answer 4

No. KVM provides low-level virtualization but relies on user-space tools (e.g., QEMU or libvirt/virsh) to create and manage VMs.

Question 5

What tools are commonly used with KVM to manage virtual machines?

Answer 5

User-space tools such as QEMU and libvirt/virsh are used to build, configure, and manage VMs when using KVM.

Question 6

At what layer does KVM handle virtualization?

Answer 6

KVM handles low-level virtualization directly on the host hardware (CPU and memory).

Question 7

What is QEMU and how does it relate to virtualization?

Answer 7

QEMU (Quick Emulator) is a user-space application that emulates full hardware systems and can run virtual machines, independently or accelerated by KVM.

Question 8

Can QEMU run virtual machines without KVM?

Answer 8

Yes. QEMU can fully emulate hardware without KVM, though performance is better when paired with KVM for hardware acceleration.

Question 9

Which components can QEMU emulate?

Answer 9

CPU, hard drive (storage), USB controller, and network card, among others.

Question 10

Who is responsible for building and managing the VM environment, KVM or QEMU?

Answer 10

QEMU is responsible for building and managing the VM environment (with libvirt/virsh often used for orchestration).

Question 11

What runtime configuration options does QEMU provide when creating VMs?

Answer 11

RAM allocation, disk images, network interfaces, and graphical output (display).

Question 12

What is the key difference between KVM and QEMU?

Answer 12

KVM provides core hardware virtualization but no VM management; QEMU manages the VM environment and can function independently but benefits from KVM acceleration.

Question 13

What do you get when you combine QEMU with KVM?

Answer 13

Full virtualization with enhanced performance through hardware acceleration.