Virtualization is the process or a technique which can create a virtual version of IT datacenter components such as Compute, storage and network etc. Hypervisor is one of the commonly used virtualization technology to create virtualized IT infrastructures. It is the important technology and is the main driver of cloud based infrastructure. Hypervisor is widely used by many cloud service providers to virtualize the traditional hardware IT infrastructure and offer them as one or more Cloud Services.
In the previous post we learned fundamental basics of Cloud Computing, models and services. In this post we will learn below topics about Hypervisor – the core concept of Cloud
- What is a Hypervisor
- Physical components that creates Datacenter Infrastructure
- Virtual Components that creates Cloud Infrastructure
- How to create a Virtualized Cloud Infrastructure
- Benefits of virtualization in a cloud environment
- How to connect to a Virtualized Infrastructure
Virtual Components that creates Cloud Infrastructure
Similar to the physical components, following virtual components helps a virtual server to perform its tasks, store data and communicate via network with the other virtual servers. The following virtual components form a virtual IT infrastructure
- Virtual Compute components
- Virtual Network components
- Virtual Storage components
Virtual Compute components
Virtual shared Memory
- A pool of RAM can be created and shared through the hypervisor to the VMs. This can allow for memory to be allocated as needed and reclaimed later when the additional memory is no longer needed.
- Memory can be provisioned for growth and ordered by the cloud consumer from the cloud provider on the fly on demand.
- As with shared networking and memory, the CPU or processing component has been virtualized and can be allocated as requested or required by the cloud computing consumers.
- CPU processing power can be elastic in that it can be created and used when additional processing power is needed and returned after the period of higher demand subsides.
Virtual Network components
- Virtual network interface cards (vNICs) are the virtualized equivalent of a standard Ethernet LAN NIC installed in a server. The vNIC is installed on the virtual machine, and the operating system sees that as a connection to a real LAN.
- Multiple vNICs can be installed on each virtual server. The vNIC will need to be configured on a VM in the same manner as a standard NIC installed in a bare-metal server to setup the IP address, the subnet mask, and the default gateway address.
- Many networking components such as virtual routers, virtual firewalls, and virtual load balancers may be installed and are often implemented as a VM running on a Type 1 hypervisor.
- A virtual switch is a software representation of an Ethernet switch that provides the Ethernet interconnection from the VMs to the network.
- All vNICs are connected to this virtual switch and, in turn, all LAN traffic destined to the outside world is forwarded out of the hardware NIC on the server to an external hardware switch or router in the datacenter.
- The virtual switch configuration utility will include options such as if the network is bridged, routed, or if NAT is being used and must be configured based on the network requirements.
- It is a Virtual network with a common endpoints of servers to provide a separate Layer 2 container for each IP subnet. All devices in the same VLAN communicate as if they were all directly connected to each other.
- This approach allows a datacenter communications network to be segmented into many VLANs and to use a common switch hardware platform.
- Each server’s vNIC must be assigned an ID that is used to bind to a specific interface’s VLAN ID that matches the configuration of the datacenter LAN. VLANs will be in the numeric range from 1 to 4096.
Virtual Storage components
- A virtual disk is an image that is presented to the guest VM as an actual hard drive. These virtual disks can be located either locally on the server.
- The virtual disk will have common configuration parameters, such as storage limits that can be defined and SCSI/SATA IDs.
- A virtual disk will contain all of the data that would be stored on a physical hard drive in this virtual disk or hard drive.
Also Read: What is Network Virtualization
- It is a common storage switching fabric and divide it up into many individual storage networks by creating a virtual storage area network (VSAN).
- All ports that are in the same VSAN can communicate with each other and share common SAN fabric services. All virtual server host bus storage adapters are configured to be in the same VSAN as the remote storage arrays and controllers they are accessing.
- The host bus adapter for storage networking and the storage controller’s interfaces must be bound in the same VSAN to access storage resources from a virtual server.
- VSANs must be assigned IDs and have the same 1-4096 number range that Ethernet VLANs use.