VMware is the leader in providing different software and applications for virtualization. The products of VMware can be categorized into two levels, server applications and desktop applications. It is useful for running multiple applications and operating systems on a single computer and is used to get high productivity from very few servers. It can also speed up the new application deployments by simplifying IT management.
Virtualization is defined as the process of creating virtual versions of storage devices network devices, servers on a physical host. There are mainly four types of Virtualization. Presentation Virtualization Storage Virtualization Application Virtualization Network Virtualization
An agent, which enables communication between VC and ESX server is called vCenter Agent. It is installed on the ESX Server.
The Server Software provided by VMware are of 3 types: VMware ESXi Server VMware Server VMware ESX Server
A virtualization interface in between ESXi host and Virtual Machine that stores VMs is called VMKernel. It allocates all the ESXi host resources to VMs such as CPU, memory, storage, etc. It can also control the special services like Fault tolerance, vMotion, traffic management, NFS, and iSCSI. While accessing these particular services, the VMKernel port should configure on ESXi server using a standard vSwitch. The hosted VMs cannot communicate with the ESXi server without using VMKernel.
A virtualization layer that enables different operating systems in sharing a single hardware host is known as Hypervisor. Each VM or operating system can be allocated in a physical resources CPU, memory, storage, etc. Mainly there are two types of Hypervisors: Bare-Metal Hosted Hypervisor
Fault Tolerance(FT) is referred to as one of the prominent components in VMware vSphere. When ESXi host fails, then FT provides the VMs availability. It can support 64GB memory up to 4vCPUs. It requires 10GB NIC for configuration because of its bandwidth-intensive. It can create the entire VM copy, such as compute, storage, and memory.
Fault Tolerance logging is an option in the settings of VMKernel port, which is almost equal to Vmotion option of the VMKernel port.
VMware Distributed Resource Scheduler (DRS) balances resources across different hosts under the resource pool or cluster. It enables the rules and policies in deploying the funds, and those resources must be prioritized to VMs.
The following are the components that are used in VMware infrastructure: ESX Server host (In the lower layer) Virtual Center Server (tracking VM associated images) VMware infrastructure client (enables the communication of client with applications of the user) Web-browser (Accessing Virtual Machines) License Server (Preparing servers in providing applications’ license) Database Servers
The .vmdk file is known as a disk descriptor file which is used to describe the memory and size of the virtual disk file. This file contains -flat.vmdk file name in association with hard drive adapter, heads, drive sectors, cylinders etc.
VMware VMotion is used to migrate the virtual machine running with zero downtime from one physical server to another. It can automatically allocate the resource pools for maximum utilization of hardware. Without any scheduled downtime, it can perform hardware maintenance. It can also migrate the virtual machines from underperforming or failing servers.
Below are the prerequisites in configuring Vmotion: Every host should meet the requirements of shared storage. Every host must be licensed correctly Shared storage must be on the Storage Area Network (SAN), otherwise implement by using NAS, SAN, and iSCSI. Every host must meet the requirements of networking. The configuration of VMsKernel should happen on every host. While migrating the workloads, use 10 GigE adaptors. Jumbo frames are very much necessary to get the best performance from VMotion.
VCloud Suite is used to combine the multiple components of VMware to give the capabilities of cloud infrastructure complete set in a single package, including disaster recovery, virtualization, application management, data centre services, etc.
The storage availability in VCloud Suite includes: Storage VMotion: It employs proactive storage migration to decrease the I/O bottlenecks of virtual machine storage. Data Protection: It deploys recovery and back-up tool based on the EMC Avamar. Storage DRS: Based on the I/O latency and storage capacity, the storage DRS balances the Virtual Machines. Application HA: It is used to get the high availability on specific applications.
VMware HA (High Availability) is used to configure on the cluster and works in host levels. A High Availability cluster will restart and migrate all the VMs that running under the host level. VMware HA detects and monitors all the hosts of the ESX server.
VMware HA (High Availability) enabled per cluster while VMware FT (Fault Tolerance) enabled per VM basis. In the case of VMware FT, there is no downtime, whereas VMware HA can be powered on and restarted.
The following are the new features in the latest version of vSphere: Virtual Machine Enhancement vSphere storage Enhancement ESXi Hypervisor Enhancement vCenter Server Enhancement vSphere Networking Enhancement
In Virtual Machines, the “point in time image” is referred to as a Snapshot. It contains an image of RAM and VMs disk. By using Snapshot, we can go back to the VM at a point of time as you wish. The functionality of the Snapshot can be used to perform VMs image-level backups.
Virtual Desktop Infrastructure (VDI) is used to connect the end user’s desktop with the help of a thin client. The end-user also can connect the desktop using VMware Horizon view.
CLONE TEMPLATE Clone is defined as the copy of Virtual Machine. A Template is termed as the master copy of Virtual Machine. It can be made when VM is powered on. It can be converted back to the VM to update the base machine. We cannot convert back the cloned VM. A Template can convert back to the VM. With the help of parent virtual machines, a linked clone can share virtual disks. It is possible to convert clone into a template, but not possible to Virtual Machines into a template when the machine is powered on. A full clone doesn’t share anything with VMs and it is independent of parent VMs. A Template cannot be powered on or edited. It is very difficult to change the ordinary VM.
Web browser Interface Setting configuration in a simple wizard Maintenance of Virtual Machines is very easy
The following are the three main uses of VMware Workstation: VMware workstation is used to save the OS configuration (existing) in Virtual Machine form. It helps in running more than one operating system in a single system. It allows in working in different Operating Systems without switching among them.
Virtual Distributed Switch (VDS) is acting as a single switch which is responsible for providing administration and central provisioning for the virtual network. Benefits of VDS: Monitoring Central Provision and Central Administration
Service Console Port Group Virtual Machine Port Group VMKernel Port Group
Parameter ESX ESXi Troubleshooting Done by Service Console Done by ESXi Shell Secure Syslog Disabled Enabled Jumbo Frames Supported Supported Boot from SAN Supported Supported Scripted Installation Supported Supported Deployment using Auto Deploy Not Supported Supported vSphere Web Access For Experimental basis For Complete Management Lockdown mode Not present Present Latest Version ESX 4.1 ESXi 6.7 Service Console Present Removed Authentication of Active Directory Supported Supported Network Management Interface Service Console ESXi Shell Hardware Monitoring Third-Party Agents CIM providers Software Patches and Updates Supported on Linux OS Only a few Patches and Updates vMA Support Available Available Custom Image Creation Not Supported Supported Command-Line Administration esxcfg esxcli VMKernel Network Storage Connectivity, Fault Tolerance, vMotion Management Network, Storage Connectivity, Fault Tolerance, vMotion, iSCSI
SWAP /opt /var /home /-root /var/core /tmp
At the time of creation, the Virtual Machine nics with MAC address is stored in .VMX file. The packet doesn’t allow the incoming traffic to the Virtual Machine if it doesn’t match with MAC address of .VMX file.
Virtual LAN (VLAN) is used to break the Broadcast traffic into a lot of logic groups. VLAN separates one broadcast domain into many tiny pieces instead of using one physical switch for compromising one domain.
In vSphere, there are mainly three types of VLAN tagging. Virtual Switch Tagging (VST) External Switch Tagging (EST) Virtual Guest Tagging (VGT)
There are three types of Load balancing policies are available for vSwitch Route Based Source MAC hash Route Based on originating virtual switch ID Route Based on IP hash
There are two types of settings in Network Failover Detection: Link Status only Beacon Probing Link Status only: It depends on the link status of the network adapter. It detects switch power failures and cable pulls, but it cannot detect the errors in a configuration such as blocking of spanning tree, wrong VLAN misconfiguration etc. Beacon Probing: It listens to beacon probes and send Ethernet broadcast frames to detect the failure network connections of upstream. Beacon Probing also detects many other failures that were not detected by Link Status.
When the user migration gets suspended or powered off, then it is called as the Cold Migration. When the user migration is running on a powered virtual machine, then it is known as Hot Migration.
The following are the drawbacks in VMware virtualization: It requires high-end servers which leads to more expensive. To buy any resources, it needs substantial investment. It requires various types of technologies for implementation.
Platform Services Controller is first introduced in VMware vSphere version 6 that handles the security functions of infrastructure. PSC has three main components: VMware Certificate Authority Single Sign-On Licensing service
Mainly there are three disk types in VMware vSphere: Eager Zeroes (Thick Provision): It is used in VMware Fault Tolerance. The disk space requirement is allocated at the time of creation to VMs. When compared to other disk formats, this Eager Zeroes thick provision takes a lot of time in creating a virtual disk. Lazy Zeroes (Thick Provision): In this disk format, every virtual disk can be created by default. There is an allocation of physical space for Virtual machines when the disk is created. This Lazy Zeroes thick provision can’t be converted into thin. Thin Provision: Thin provision provides the disk space allocation to Virtual Machines. The disk size will increase in proportional to the data size.
VVoL (Virtual Volume): It is a concept of new disk management of Virtual Machine in vSphere 6.0 version which enables the operations of array-based at the virtual disk level. Virtual Volume can be created automatically when the virtual disk is created. RDM (Raw Device Mapping): Raw Device Mapping is a file, which is stored in the VMFS volume acts as a proxy for the devices which are in natural physical form. RDM stores the data of virtual machines on LUN. NFS (Network File System): NFS is a file-sharing protocol which is used to communicate with NAS (Network Attached Storage) devices. It connects to a network and gives file aces services to the hosts of ESXI.
There are two configuration options in VSAN: Hybrid All-Flash Hybrid: Uses both magnetic and flash-based disks for storage. The magnetic disks are used for storage or capacity, while flash-based drives are used for cash. All-Flash: It uses flash for both for storage and caching.
The following are the three steps required to convert a physical machine into a virtual machine: Initially, an Agent should be installed on the physical machine Along with the Converter plug-in, a VI client must be installed Needs a server to Export/Import the virtual machine
VMware DPM: VMware DPM (Distributed Power Management) is a feature of VMware DRS which is used to monitor the cluster resources. VMware DPM shutdowns the un-used hosts and consolidates the workloads when the resources get decreased. If the resources get increased, then it automatically power-on the hosts that are not being used. ESXi Shell: ESXi Shell is a command-line which is used to repair the ESXi hosts. It can be accessed through vCenter Server disable/enable, DCUI, and SSH.