Data Center Virtualization Quiz

Cloud and Virtualization Concepts

• Virtualization is a technology that goes between physical hardware and operating systems to create copies of a device.
• Modern computing is more efficient due to virtualization, which is used for mobile, personal, and cloud computing.
• Virtualization can also be used personally.
• The content covers the benefits of virtualization, explaining virtualization, virtual machines, and hypervisors; typical data center components that are virtualized; and VMware technology in the industry.

Why Learn Virtualization

• Modern computing is more efficient due to virtualization.
• Virtualization can be used for mobile, personal, and cloud computing.
• Virtualization can be used personally.

Key Concepts

• Virtualization: A technology that sits between physical hardware and operating systems, enabling the creation of copies of a device. Virtualization enhances efficiency in various computing contexts.

• Virtual Machines (VMs): Virtualized representations of physical machines. VMs consist of a set of files.

• Hypervisors: Software that creates and manages virtual machines. Hypervisors utilize virtual hardware to create a virtual machine. Type 1 hypervisors are "bare metal" while Type 2 hypervisors are "hosted".

• Datastores: Logical storage structures for VMs – physical storage is partitioned logically.

• VM files VMs are stored as .vmdk files on datastores, with configuration files (.vmx).

• Snapshots: Saved states of VMs, saved as files (.vmx) in the VM folder, capturing VM disk states, memory contents, and settings.

Virtual Machines (VMs)

• Virtualization creates virtual hardware by cloning physical hardware.
• Hypervisors employ virtual hardware to generate virtual machines.
• VMs are sets of files.
• With a hypervisor, a single computer can concurrently run multiple operating systems.

The Hypervisor

• Hypervisor software is installed atop hardware.
• Type 1 hypervisors (e.g., VMware ESXi) operate on bare metal hardware.
• Type 2 hypervisors (e.g., VMware Workstation) operate on top of a host operating system.

Virtual Machine Files

• VMs can be exported and moved across hosts.
• Files are created by the hypervisor and are stored in a directory.
• Specific files include log files (.log), disk files (.vmdk), snapshot files (.vmsd & .vmsn), and configuration files (.vmx). Log files keep track of VM activity; disk files store VM disk drive content. Snapshot files record VM snapshot states. Configuration files contain information such as VM name, BIOS, guest OS, and memory.

What is a Snapshot?

• Snapshots are used to save the state or progress of a VM.
• Snapshots are saved as files in the VM folder.
• Snapshots capture disk state, memory contents, and VM settings.

Data Center Components

• A data center's core components are compute, storage, and networking.
• Data centers accommodate complex hardware infrastructure supporting virtualization and data processing.
• Supporting large data volumes is a critical function of data centers.

Compute Systems

• Compute systems in data centers manage applications using operating systems.
• PCs generally feature user-friendly interfaces, whereas servers prioritize program execution.
• Server types such as tower, blade, and rack-mounted servers are common in data centers.

Networks

• Networks in a data center facilitate communication among devices.
• Common hardware for networking includes Ethernet cables, switches, Network Interface Cards (NICs), and routers.

Storage

• Data center storage systems prioritize availability and redundancy.
• RAID (Redundant Array of Independent Disks) combines multiple hard drives for increased storage capacity and data integrity via mirroring, striping, and parity methods.

Storage Types

• Block-level storage: Data is written and accessed from storage volumes (blocks).
• File-level storage: Data is written to disks but accessed through the file system.
• DAS (Direct Attached Storage): Storage devices are connected directly to servers.
• NAS (Network Attached Storage): Storage devices are networked, accessible to servers.
• SAN (Storage Area Network): A dedicated network for storage devices, accessed by servers on the same network.

Storage Protocols

• Protocols like SCSI, FC, FCoE, and iSCSI enable device communication in data centers.
• Protocols are associated with applications based on scale (medium-sized blade servers through large enterprise servers)

Storage Provisioning

• Thick provisioning allocates space equal to the physical space on storage.

Virtual Data Center

• Virtualization enhances data center hardware efficiency, allowing for higher application availability.
• Virtualized resources can be monitored centrally.
• Software-defined data centers (SDDCs) pool data center resources to construct a virtual environment.

VMware vSphere

• vSphere is virtualization software for enterprise data centers.
• vSphere includes tools such as ESXi (Hypervisor),vCenter Server (Management Software) and vSphere Client (GUI).
• ESXi operates directly on physical hardware while vCenter is a management server, controlling host servers and VMs.

vSphere Components

• ESXi (Type 1 hypervisor) is installed directly on physical servers.
• vCenter manages ESXi and other data center components for virtualization.
• vSphere Client is software for managing hosts and VMs graphically.

Server Virtualization

• Server virtualization increases data center efficiency by consolidating multiple VMs on a single server.
• Server virtualization decreases hardware requirements by distributing resources to customers.

Storage Virtualization

• Storage virtualization distributes storage to VMs through physical storage partitioning.
• Logical storage units (LUNs) create datastores for efficient VM storage management.
• VMs access storage through .vmdk files with settings in .vmx files.

Network Virtualization

• Network virtualization uses virtual switches to create a single virtualized network from multiple physical networks.
• VLANs (Virtual Local Area Networks) isolate network segments.
• vSwitches manage virtual devices to communicate within a virtualized network.

Types of Virtual Networks

• NAT (Network Address Translation): VMs are assigned a translated IP address from the host's IP for private networked communication.
• Host-only networks: VMs use a private network that does not translate IPs for connections outside of the host machine.

Application and Desktop Virtualization

• Virtualized applications provide tailored environments, handling specific system requirements.
• Desktop virtualization helps mobile workforces access computing resources without physical hardware.
• VMware Horizon manages resources to create virtual desktop environments in data centers.

What is the Cloud?

• Cloud computing delivers shared resources (software and data) on-demand via the internet.

Types of Cloud Computing

• Software as a Service (SaaS), Platform as a Service (PaaS), and Infrastructure as a Service (IaaS) are fundamental cloud service models.

Cloud Deployment Models

• Public, Private, Community, and Hybrid Clouds are distinct cloud deployment models based on resource ownership and access.

VMware Solutions

• VMware offers various solutions tailored for businesses, promoting data center efficiency, application access, and disaster readiness.

vMotion

• vMotion moves running VMs between ESXi hosts without service interruption.
• This boosts the availability of data and resources.

Storage vMotion

• Storage vMotion moves VM disks and configurations between data stores.
• It helps enhance storage availability.

High Availability (HA)

• HA clusters servers, enabling VMs to restart on alternate hosts in case of server failure. Maintaining uptime during hardware malfunctions.

Fault Tolerance (FT)

• FT creates secondary copies of VMs and their files on a different server and datastore.
• Transfers between servers are seamless and unnoticed.

Replication

• Replication makes copies of VMs in separate locations, a critical disaster recovery and protection resource.

vCloud Automation Center

• vCloud Automation Center is software that automates and manages cloud services, helping with infrastructure delivery, individual access to services, and service delivery diversification.

CloudHealth

• CloudHealth offers insights into cloud performance aspects inclusive of cost analysis, usage tracking, and security assessments.
• CloudHealth helps monitor resources like CPU, memory, and disk usage within virtualized servers, facilitating IT efficiency and risk avoidance.