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23-459: Like all virtual appliances , the main component of an AMI is a read-only filesystem image that includes an operating system (e.g., Linux , Unix , or Windows ) and any additional software required to deliver a service or a portion of it. An AMI includes the following: The AMI filesystem is compressed, encrypted, signed, split into a series of 10 MB chunks and uploaded into Amazon S3 for storage. An XML manifest file stores information about

46-451: A compound annual growth rate (CAGR) of 22.6% from 2023 to 2030. This growth is primarily driven by the adoption of cloud-based infrastructure within the Banking, Financial Services, and Insurance ( BFSI ) sector, which employs these technologies to enhance scalability and reduce operational costs. The UK Government encourages departments to use public cloud solutions as a first option. IaaS

69-416: A public cloud (where users share hardware, storage, and network devices), a private cloud (users do not share resources), or a hybrid cloud (combination of both). The US National Institute of Standards and Technology (NIST) defines infrastructure as a service as: The capability provided to the consumer is provision processing, storage, networks, as well as other fundamental computing resources where

92-415: A direct route for traditional on-premises applications to be rapidly redeployed in a software as a service (SaaS) mode – without requiring major application re-architecture for multi-tenancy . By decoupling the hardware and operating system infrastructure provider from the application stack provider, virtual appliances allow economies of scale on the one side to be leveraged by the economy of simplicity on

115-423: A software appliance on a virtual machine and packaging that into an image creates a virtual appliance. Like software appliances, virtual appliances are intended to eliminate the installation, configuration and maintenance costs associated with running complex stacks of software. A virtual appliance is not a complete virtual machine platform, but rather a software image containing a software stack designed to run on

138-512: A virtual machine platform which may be a Type 1 or Type 2 hypervisor. Virtual appliances are provided to the user or customer as files, via either electronic downloads or physical distribution. The file format most commonly used is the Open Virtualization Format (OVF). It may also be distributed as Open Virtual Appliance (OVA), the .ova file format is interchangeable with .ovf. The Distributed Management Task Force (DMTF) publishes

161-559: A virtual-machine disk-image library, raw block storage , file or object storage , firewalls, load balancers, IP addresses, virtual local area networks (VLANs), and software bundles. IaaS-cloud providers supply resources on-demand from the large pools of equipment installed in data centers . For wide-area connectivity, customers can use either the Internet or carrier clouds (dedicated virtual private networks , VPNs). To deploy their applications, users install operating-system images and

184-403: Is Linux containers , which run in isolated partitions of a Linux kernel that runs directly on the physical hardware. Containers are isolated, secured and managed using Linux cgroups and namespaces. Containerisation offers higher performance than virtualization because there is no hypervisor overhead. The global IaaS market is projected to reach a value of $ 411.9 billion by 2030, expanding at

207-470: The Amazon Machine Image format. Amazon EC2 reduces the cost-barrier to the point where it becomes feasible to have each customer of the hosted service provisioned with their own virtual appliance instance(s) rather than forcing them to share common instances. Prior to EC2, single-tenant hosted models were too expensive, leading to the failure of many early ASP offerings. Furthermore, in contrast to

230-608: The Windows Server 2003 and Windows Server 2008 operating systems to the list of available operating systems . As of December 2010, it has also been reported to run FreeBSD ; in March 2011, NetBSD AMIs became available. In November 2012, Windows Server 2012 support was added. Amazon has its own Linux distribution that is largely binary compatible with Red Hat Enterprise Linux . This offering has been in production since September 2011, and in development since 2010. The final release of

253-446: The AMI, including name, version, architecture, default kernel id, decryption key and digests for all of the filesystem chunks. Current AMIs are available for hardware virtualized machines (HVM) where the operating system is installed as it would be on real hardware. With the still available older paravirtualized virtual machines (PV), an AMI did not include a kernel image, only a pointer to

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276-485: The OVF specification documentation. Most virtualization platforms, including those from VMware, Microsoft, Oracle , and Citrix, can install virtual appliances from an OVF file. Virtualization solves a key problem in the grid computing arena – namely, the reality that any sufficiently large grid will inevitably consist of a wide variety of heterogeneous hardware and operating system configurations. Adding virtual appliances into

299-423: The application in place on the hosted infrastructure. Infrastructure as a service Infrastructure as a service ( IaaS ) is a cloud computing service model where a cloud services vendor provides computing resources such as storage, network, servers, and virtualization (which emulates computer hardware). This service frees users from maintaining their own data center , but they must install and maintain

322-410: The application software on the cloud infrastructure. Users patch and maintain the operating systems. IaaS services are typically billed as a utility: cost reflects the amount of resources allocated or consumed. Typically, IaaS involves the use of a cloud orchestration technology such as OpenStack , Apache CloudStack , or OpenNebula . It manages the creation of a virtual machine (VM) and decides on

345-448: The cloud user even though the cloud user may be the owner of the virtual appliance. However, challenges may arise with the transfer of virtual appliance ownership or transfer of virtual appliances between cloud data centers. In this case, virtual appliance copy or export/import features can be used to overcome this problem. With the rise of virtualization as a platform for hosted services provision, virtual appliances have come to provide

368-407: The consumer is able to deploy & run arbitrary software, which can include operating systems and applications. The consumer does not manage or control the underlying cloud infrastructure but has control over operating systems, storage, & deployed applications; and possibly limited control of select networking components (e.g., host firewalls). IaaS clouds often offer additional resources such as

391-514: The default kernel id, which could be chosen from an approved list of safe kernels maintained by Amazon and its partners (e.g., Red Hat , Canonical , Microsoft ). Users could choose kernels other than the default when booting an PVM AMI. When it launched in August 2006, the EC2 service offered Linux and later Sun Microsystems ' OpenSolaris and Solaris Express Community Edition . In October 2008, EC2 added

414-572: The hypervisor (i.e. physical host) in order to start it. A hypervisor runs virtual machines (VMs) as guests. Pools of hypervisors in the cloud operational system can support large numbers of virtual machines and the ability to scale services up and down according to demand by customers. Hypevisors include Xen , Oracle VirtualBox , Oracle VM , KVM , VMware ESX /ESXi, or Microsoft Hyper-V . It also enables VM migration between hosts, allocates storage volumes, and attaches them to VMs that track usage information for billing. An alternative to hypervisors

437-421: The multi-tenancy approaches to SaaS, a virtual appliance can also be deployed on-premises for customers that need local network access to the running application, or have security requirements that a third-party hosting model does not meet. The underlying virtualization technology also allows for rapid movement of virtual appliances instances between physical execution environments. Traditional approaches to SaaS fix

460-488: The operating system and application software. Iaas provides users high-level APIs to control details of underlying network infrastructure such as backup, data partitioning, scaling, security and physical computing resources. Services can be scaled on-demand by the user. According to the Internet Engineering Task Force (IETF), such infrastructure is the most basic cloud-service model. IaaS can be hosted in

483-543: The original Amazon Linux is version 2018.03 and uses version 4.14 of the Linux kernel . Amazon Linux 2 changed from System V init system to systemd boot. It was announced in June 2018, and is updated on a regular basis. Virtual appliance A virtual appliance is a pre-configured virtual machine image , ready to run on a hypervisor ; virtual appliances are a subset of the broader class of software appliances . Installation of

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506-474: The other. Traditional approaches to SaaS, such as that touted by Salesforce.com, leverage shared infrastructure by forcing massive change and increased complexity on the software stack. A concrete example of the virtual appliances approach to delivering SaaS is the Amazon Elastic Compute Cloud (EC2)—a grid of Xen hypervisor nodes coupled with the availability of pre-packaged virtual appliances in

529-424: The picture allows for extremely rapid provisioning of grid nodes and importantly, cleanly decouples the grid operator from the grid consumer by encapsulating all knowledge of the application within the virtual appliance. Virtual appliances are critical resources in infrastructure as a service cloud computing . The file format of the virtual appliance is the concern of the cloud provider and usually not relevant to

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