VMWARE INTERVIEW QUESTIONS LATEST

What does ESXi stand for?

ESXi stands for ESX Integrated. VMware ESXi is a type-1, enterprise-class hypervisor which easily installs on to your server and divides itself into multiple virtual machines. It isn’t a software application, although it includes and integrates vital OS components, such as a kernel.

What is VMKernel? What is the VMkernel port used for?

The VMkernel is the interface between virtual machines (VMs) and the physical hardware of the system. The responsibility of VMkernel is scheduling CPUs, allocating memory and providing other hardware abstraction with other operating systems (OS) services.

Virtual machines cannot communicate with the ESXi server without VMKernel, so that’s why it’s very important for VMs.

VMkernel port, also called VMkernel adapter, is a type of VMkernel network interface that works as a service provider used by the ESXi host to communicate with the VMware-based infrastructure. These adapters or ports are created according to the type of services required by vMotion, Fault Tolerance, Management or perhaps vSAN etc.

What is VMotion? Why is it used?

VMotion could also be a key enabling technology for creating the dynamic, automated, and self-optimizing data centre.

We used VMware VMotion because it enables the live migration of running virtual machines from one physical server to a special one with zero downtime, continuous service availability, and complete transaction integrity.

What is Port-group? VM port groups are how we will create logical rules round the virtual ports that are made available to VMs. It’s common to make a port group >for every VLAN and network subnet that you simply want to present to your VMs.

What is vSwitch in VMware? vSwitch is the software-based virtual networking switch used to connect virtual machines to the ESXi host and it also provides the connectivity between the virtual machines on that virtual switch. vSphere Standard Switch is referred to as vSwitch. Each ESXi host requires its own vSwitch.

How does vMotion work in the background? The Virtual Machine Memory state is copied over the Vmotion Network from the source Host to the Target Host. Users still access the virtual machine and potentially update memory pages. A list of modified pages in memory is kept during a memory Bitmap on the source host.

What happens if VMotion fails? VMotion will fail if the target host does not have enough memory to satisfy the reservation of the virtual machine. If you want to fix this, migrate the virtual machine to another ESXi host that can provide the guaranteed memory for the VM or reduce the memory reservation of the virtual machine.

What is the hypervisor and its types? A hypervisor may be a virtualization layer that permits multiple operating systems to share one hardware host. Each operating system or Virtual Machine is allocated physical resources such as memory, CPU, storage etc by the host. There are two types of hypervisors.

Hosted hypervisor – works as application i.e. VMware Workstation Bare-metal – is virtualization software i.e. VMvisor, Hyper-V which is installed directly onto the hardware and controls all physical resources. We have got tons of features like VMotion, DRS, SMP, etc, but why do we like HA? We’d like this because we want our services running without interruption. Assume like, for a couple of reasons if anyone of the ESX server within the cluster goes down suddenly, what happens to the virtual machines which are running thereon particular server? Do they continue to run or go down?

Yes, they also go down. But with the help of VMware HA, these VM’s are often restarted immediately on the other ESX servers within an equivalent cluster. But here, you’ll get a downtime of 5 –10 mins because a server crash is an unexpected thing.