Written by Zakir Hossain, CS Graduate (OSU) CEO, Data Group Fed Certifications: PFA (Programming Foreign Assistance), COR (Contracting Officer), AOR (Assistance Officer) Oracle Certifications: OCP (Oracle Certified Professional), OCA (Oracle Certified Associate), Oracle RAC-Admin, Oracle Backup/Recovery-Admin, Oracle Performance/Monitoring-Admin, Oracle WebLogic Admin Microsoft Certifications: MCDBA (Microsoft Certified Database Admin), MCITP: SQL Database Admin, MCITP: SharePoint Admin System Admin Certifications: MCITP: Windows Server 2012 Admin, RHCSA (Red Hat Certified System Admin) Programming Certifications: SCJP (Sun Certified Java Programmer) Other Certifications: Security+, ITIL V3 Please Read License Agreement carefully.. You are allowed to use this document only for your pers onal and job related purposes. Under no circumstances, you are not allowed to share this document with any institute/organization, individuals, business entity, and students either current or discontinued without written permission. It also prohibited modifying or altering any parts of this document either for commercial or training purposes. It is 100% prohibited and violation of Federal Law of Intelligence Product. A serious action will be taken if it is violated. If you need our books, notes, documents, please contact directly with Zakir Hossain (ZHossain@DataGroupUSA.com, 703-203-2325) Virtualization means a technique or technology of creating a virtual version of something. Examples: virtual computer, virtual hardware, virtual storage, virtual network, virtual CDROM and many more. So, we can create virtual version of server for which can be used for Database Server like SQL Server Database server, Oracle Database server, MySQL Database server, File Server, Application Server, Web Server and so on. Another example of virtualization is partitioning a hard drive is considered virtualization because you take one physical drive and partition it to create two or more separate hard drives. In IT industry, virtualization refers to creation of a virtual machine that acts like a real computer with an operating system. Software runs on virtual machines is separated or different from the underlying physical machine/computer. For example, a computer that is running on Microsoft Windows, it may host a virtual machine may have different or same operating system like UNIX, Red Hat Linux, Ubuntu Linux or Windows Operating System. Host Machine: Host machine is the actual machine on which the virtualization takes place Guest machine: Virtual machine is called Guest Machine. So, again, Host and guest are used to distinguish between the Physical machine and Virtual Machine.
Hypervisor or Virtual Machine Manager: The software that creates a virtual machine on host machine is called a hypervisor or Virtual Machine Manager. It is also used to maintain or manage and monitor the virtual machines. Migration: Either can take a snapshot, or copy of a VM and move onto another host machine with its own hypervisor, and then resume on the new host. This is called migration. Examples of Virtualization: Virtualization technology can be used for virtualizing many things like Storage virtualization: Used to create virtual disks and can be used by servers, application servers, database servers, backup server and so on. So, space can be allocated to servers as long as there is a network between the server and the storage Server virtualization: It is partitioning a physical server into smaller virtual servers Network virtualization: Uses physical network resources through a logical division of a single physical network Data Virtualization: Presentation of data, independent of underlying database systems Database Virtualization: It is between storage and application layers Virtual disk drive: Virtual file system: Virtual memory: Virtual Server/Computer/Desktop Virtual Machine/Server: Virtualization allows us to run multiple independent operating systems on the same physical server. Although each of these operating systems share the physical resources available in that physical server, they are each fully independent and have no knowledge of the other operating systems running on the same physical machine. Multiple separate operating systems (referred to as virtual machines) can now independently run at the same time on one physical server, and an operating system is no longer dependent on that specific physical machine. Each virtual machines and applications running inside the Virtual Machines access the same set of compute resources, such as CPU or memory, network adapter, and storage. Example of major hypervisors: VMware: vsphere Microsoft: Hyper-V OpenStack
Oracle VM Red Hat Enterprise Virtualization Citrix XenServer Benefits: Cost reduction Independent consolidation/ consolidating: High Availability Disaster Recovery Flexibility Disk/Storage/SAN Storage allocation to Virtual Machine: - Storage can be from SAN or NAS - A SAN LUN is carved off and presented to all of the physical servers in the virtualization cluster - Hypervisor can format and manage it for virtual disks or it can be passed through meaning Raw Device Mapped disk (RDM) and the hypervisor can directly connected to the virtual machine - A virtual disk is a file placed on a shared file system managed by the hypervisor (referred to as a datastore), and provides the most flexibility from a hypervisor standpoint Shared Resources: Hardware - HD, Sound card, Network, memory, USB, CDROM, CPU, Mother board,. All these shared resources are called virtual vcpu, vmemory, vnetwork, vhd,
Not shared: Software: OS, Office, PDF, SQL Server, SharePoint, Oracle, MySQL requires separate installation and configuration Cloud Computing: Cloud means internet. So, in cloud computing, we store and access data and programs over the Internet instead of computer's hard drive. Cloud computers are Remote Servers hosted on Internet to store, manage, and process data, rather than a local server or a personal computer. Cloud computing is not only about hard drive. If storing data or running programs from hard drive that is called local storage and local computing. Remote Computing: Cloud computing enables companies to use compute resources as a utility -- just like electricity -- rather than having to build and maintain computing infrastructures in-house. It is also important to keep in mind that cloud is not about having a dedicated network attached storage (NAS) or SAN hardware or server in residence. Storing data on a home or office network does not count as utilizing the cloud. However, some NAS will let you remotely access things over the Internet. So, it is about data is synchronized with other information over the Web Benefits: The big benefit does not have to deploy physical infrastructure like file and e-mail servers, storage systems, data center, storage, file server, application server, web server or shrink-wrapped software. Major benefits: Self-service provisioning: End users can spin up computing resources for almost any type of workload on-demand Elasticity: Companies can scale up as computing needs increase and then scale down again as demands decrease Pay per use: Computing resources are measured at a granular level, allowing users to pay only for the resources and workloads they use Cloud computing services Model: Cloud computing services model can be
1. Private, 2. Public or 3. Hybrid. Private cloud services are delivered from a business' data center to internal users. This model offers variety and convenience, while preserving management, control and security. Internal customers may or may not be billed for services through IT chargeback. Public cloud model: In public cloud model, cloud service provider delivers the cloud service over the Internet. Public cloud services are sold on-demand, typically by the minute or the hour. Customers only pay for the CPU cycles, storage or bandwidth they consume. Leading public cloud providers are Amazon Web Services (AWS), Microsoft Azure, IBM/SoftLayer, Verizon Terramark, and Google Compute Engine. Hybrid cloud Model: Hybrid cloud is a combination of public cloud services and on-premises private cloud with orchestration and automation between the two. Companies can run mission-critical or sensitive applications on the private cloud and at the same time can use public cloud for workloads that must scale on-demand. The goal of hybrid cloud is to create a unified, automated, scalable environment which can take the advantage of all that a public cloud infrastructure can provide, while still maintaining control over mission-critical data Cloud Computing Service Category/Types: How end users can consume cloud computing meaning how end users can subscribe cloud computing services. For an example, AT&T offers different plan for cell phone services. It has been divided into three broad service categories: 1. Software-as-a-Service (SaaS): In SaaS model, providers offer software applications over the Internet. These services are often called Web services. Users can access SaaS applications and services from any location using a computer or mobile device that has Internet access. Software-as-a-Service (SaaS), where a company subscribes to an application it accesses over the Internet. Again, a specific application or service is offered to a customer as a subscription basis. SaaS provides a way of delivering a host of software and technical services that might be cost effective, and difficult to manage as on-premise, local solutions.
For example: Microsoft Office 365, emails, Dropbox, Salesforce.com, and QuickBooks 2. Platform-as-a-Service (PaaS): In PaaS model, providers host development tools on their infrastructures. Users access those tools over the Internet using APIs, Web portals or gateway software. So, in Platform-as-a-Service (PaaS) model, it offers a platform on which they can create and deploy custom apps, databases and other business services PaaS is used for general software development and many PaaS providers will host the software after it's developed. Examples of PaaS are Amazon, Microsoft Azure, SalesForce.com, and Google App Engine. 3. Infrastructure-as-a-Service (IaaS): IaaS providers provide a virtual server instance, storage, applications and application program interfaces (APIs). So, users can migrate workloads to a virtual machine (VM). Users have an allocated storage capacity and start, stop, access and configure the VM and storage as desired. IaaS providers offer small, medium, large, extra-large, and memory- or compute-optimized instances, in addition to customized instances, for various workload needs. Example of IaaS providers are Amazon EC2, Rackspace, and Google Compute Engine. Examples of Cloud computing: There might be a local piece of software (for example, Microsoft Office 365) that utilizes a cloud computing for storage (for example Microsoft OneDrive). Microsoft also offers a set of Web apps, now called Office Online, that are online-only versions of Word, Excel, PowerPoint, and OneNote accessed via Web browser without installing anything. This makes these a version of cloud computing (Web-based=cloud). Google Drive: This storage is online and it can work with the cloud apps like Google Docs, Google Sheets, and Google Slides. This drive can be used from desktop computers; on tablets or on smartphones. Other Google's services are also considered as cloud computing: Gmail, Google Calendar, Google Maps, and so on
Apple icloud: Apple's cloud service is primarily used for online storage, backup, and synchronization of your mail, contacts, calendar, and more. All the data you need is available to you on your ios, Mac OS, or Windows device (Windows users have to install the icloud control panel). Amazon Cloud Drive: Storage that holds music like MP3s that you purchase from Amazon, and images. If you have Amazon Prime, you get unlimited image storage. Hybrid services: In this case, providers store a synced version of your files online and also sync those files with local storage. Examples: Box, Dropbox, and SugarSync all these are cloud because Synchronization allow all your devices to access the same data of the cloud computing experience, even if you do access the file locally. Backup: We are very familiar with the many backup tools for backing up documents synced through Evernote, Dropbox, and OneDrive (formerly SkyDrive) automatically moving to new machines. Maintenance: Cloud services also require maintenance. So, it depends on third-party's uptime reliability. Example: if Intuit's site is down, customers are unable to access their data in Intuit's online offerings including Quicken, QuickBooks and TurboTax. Google as a service Software as a Service: Google docs, Google sheets, Google slides, Google email service. Amazon cloud: