1.12 Virtualization Fundamentals Flashcards
Summarize virtualization fundamentals (server virtualization, containers, and VRFs). (24 cards)
What is a virtual machine?
(VM)
An OS instance that runs on virtualized hardware.
VMs allow multiple operating systems to run on a single physical server, decoupling the OS from the hardware.
Why is server virtualization used in modern data centers?
It improves resource utilization and scalability.
Virtualization allows for better hardware usage, easier management, and isolation of workloads.
What does the hypervisor do in server virtualization?
It manages hardware allocation to VMs.
Hypervisors create and manage virtual machines by providing each VM with virtualized resources.
What are the types of hypervisors?
- Type 1 (bare-metal)
- Type 2 (hosted)
Type 1: Runs directly on hardware.
Type 2: Runs on top of an existing OS.
True or False:
A hypervisor runs multiple operating systems on a single physical server.
True
Hypervisors allow for the concurrent running of multiple VMs, each with its own OS, on the same hardware.
What are the key components of a hypervisor?
- Virtual Machine Monitor (VMM)
- Virtual CPUs (vCPU)
- Virtual memory (vRAM)
- Virtual storage
- Virtual network interfaces (vNICs)
Virtual Machine Monitor: Manages VM resources.
Virtual CPUs: Allocates CPU resources to VMs.
Virtual memory: Provides memory for VMs.
Virtual storage: Manages storage for VMs.
What makes a Type 1 hypervisor preferable to a Type 2?
Type 1 is more efficient and scalable.
Type 1 hypervisors run directly on hardware, making them better for production environments due to their performance and security.
What is the process of starting a VM is often called?
Spinning up a VM
“Spinning up” refers to the process of initiating and powering on a virtual machine, allowing it to begin functioning in the virtual environment.
What is the use of a virtual machine snapshot?
It captures the current state of a Virtual Machine.
It includes the VM’s disk, memory, and settings, allowing easy rollback. Snapshots are commonly used for backup and recovery, enabling quick restoration in case of failure.
What components are commonly virtualized for each VM?
- NIC
- RAM
- CPU
NIC: Virtual Network Interface Card for network connectivity.
RAM: Virtualized memory allocated to the VM for processing tasks.
CPU: Virtual processor resources assigned to run the operating system and applications.
What are the main features of a vSwitch?
- VLAN configuration for VM ports
- VLAN trunking for physical NIC ports
- Automated configuration through virtualization software
A vSwitch allows VMs to be assigned specific VLANs or share VLANs. It supports VLAN trunking for communication between physical NICs and automates network configuration within the virtualization platform.
True or False:
A vSwitch allows communication only between virtual machines.
False
A vSwitch allows both internal communication between VMs and communication with external networks through physical network adapters (NICs).
True or False:
A virtualized data center can dynamically allocate resources.
True
Virtualized data centers use software to allocate computing resources such as CPU, memory, and storage on demand, improving efficiency and scalability.
What happens in a public cloud when a consumer requests a service?
Virtualization tools create the service.
The service runs in a data center managed by the public cloud provider.
Fill in the Blank:
The tool used to manage VMs in VMware is called ________.
vCenter
vCenter is a centralized management tool for managing multiple ESXi hosts and VMs in a VMware environment.
Define:
containerization
A lightweight virtualization running apps in containers.
Containers share the host OS kernel, making them more resource-efficient than full VMs. They are often used for microservices and application deployment.
Why is containerization preferred for microservices architecture?
- Lightweight
- Fast to deploy
- Easily scalable
- Ideal for microservices
Containers allow isolated, independent services that can be updated or scaled individually without affecting others.
What are the key benefits of using containers?
- Faster startup times
- Efficient resource usage
- Portability across environments
- Isolation for security
Containers allow for fast deployment and scaling, making them a popular choice for modern cloud-native applications.
True or False:
Containers offer stronger isolation than virtual machines.
False
VMs provide stronger isolation since each VM includes its own OS, while containers share the same host OS kernel.
List the key differences between containers and virtual machines.
- Containers share the host OS kernel; VMs run their own OS.
- Containers are more lightweight, while VMs are more isolated.
- Containers start faster and use fewer resources than VMs.
Containers are ideal for cloud-native applications, while VMs offer better security and isolation.
Fill in the blank:
The tool commonly used to manage containers is ________.
docker
Docker is a widely used containerization platform that simplifies the creation, deployment, and management of containers.
What is VRF?
(Virtual Routing and Forwarding)
A technology that allows multiple routing tables on one physical router.
Each VRF instance can be configured with its own IP routing table, enabling the same IP address space to be used for different traffic.
List the benefits of using VRF.
- Traffic isolation
- Better security and policy enforcement
- Efficient use of IP address space
- Simplified network design
VRF helps organizations manage multiple routing domains without needing separate physical routers, thus optimizing resources and improving security.
True or False:
VRFs can only be used in service provider networks.
False
VRFs can be used in both enterprise and service provider networks to create isolated routing instances and enhance security.
