VMWARE INTERVIEW QUESTIONS

VMWARE INTERVIEW QUESTIONS

Introduction

VMware is one of the leading players in the cloud computing and virtualization software industries. With the help of VMware’s server virtualization, many companies and organizations have their virtual machines and OS running on VMware’s physical server, including the United States Senate. Landing a job at VMware or any cloud computing and virtualization company can be a legitimate victory in one’s career. So, here are some of the most well-researched interview questions and answers to easily acquire a position at VMware.

VMware interview questions and answers

What is VMware, and what are its functions?

VMware is a cloud computing and virtualization software. The following are the functions of VMware:

Explain the virtualization process. 

  • Virtualization is the process of virtualizing hardware like computers by adding a layer of software so multiple operating systems can be run on one server efficiently. VMware virtualizes hardware using a hypervisor.
  •  Hypervisors add a small software layer that enables multiple parts of operating systems to run alongside each other, sharing one physical computing resource. This process is called virtualization, and the operating system instances are called virtual machines (VMs)—software functions and actions of physical computers. 

What is a hypervisor, how was it implemented historically, and how does it work?

A hypervisor is a software that adds a thin layer of software that enables different instances of an operating system to run on one physical server easily. This process is called virtualization. Before hypervisors became prevalent, most physical computers could only run one operating system (OS) at a time. This made them steady because the computing hardware only had to handle requests from that one OS. The downside of this approach was that it wasted resources because the operating system couldn’t always use all of the computer’s power despite existing in its environment. A hypervisor solves that problem. It adds a small software layer that enables multiple parts of operating systems to run alongside each other, sharing one physical computing resource. This process is called virtualization, and the operating system parts are called virtual machines (VMs)—software emulations of physical computers. 

The hypervisor, also known as a virtual machine monitor (VMM), manages these VMs as they run alongside each other at the same time. It separates VMs from each other logically, assigning each of them their own slice of the underlying computing power, memory, and storage. Because of this, the VMs will not interfere with each other, so if, for example, one OS suffers a crash or a security compromise, the others will survive. Learn more about the VMware training in Chennai for the best coaching sessions.

Explain elaborately the characteristics and requirements of hypervisors.

The following are the characteristics of hypervisors:

  • Performance. Look for benchmarks showing how well the hypervisor performs in a production environment. Consequently, the bare-metal hypervisors should support guest OS performance close to native speeds.
  • Management tools. Running VMs isn’t the only thing that must be managed when using a hypervisor. It must be maintained, audited, and cleaned to prevent “VM sprawl.” 
  • Ecosystem. Good documentation and technical support are required to implement and manage hypervisors across multiple physical servers at scale. Also, a healthy community of third-party developers can support the hypervisor with their agents and plugins that offer capabilities such as backup and restore capacity analysis and fail-over management.
  • Live migration. This helps to move VMs between hypervisors on different physical machines without interruption, which can be useful for both fail-over and workload balancing.
  • Cost. The cost and fee structure involved in licensing hypervisor technology should be considered. The cost of the hypervisor alone should not be considered. The management software that makes it scalable to support the environment of an enterprise can often be expensive. Lastly, the vendor’s licensing structure should be examined, which may change depending on whether it is deployed in the cloud or locally.

What are the benefits of using VMware products?

  • Efficient use of space and energy: VMware lets the user run more applications using fewer physical servers. Fewer physical servers require less space in the data center and less energy to power.
  • Return on investment: With VMware, users can run each application in its own OS on the same physical server and make better use of the physical server’s CPU power as opposed to running multiple applications on one OS resource.
  • Industry support: VMware has over 500,000 customers with a network of 75,000 partners and supports customers with a wide variety of add-on products and services worldwide. Find out more about Updated VMware training course syllabus to pique your interest

Describe the historical relationship between VMware and Linux. (VMware interview questions)

VMware was dependent on Linux during its startup period. The earlier version of the current hypervisor was called ESX, which had a Linux kernel, which was a central part of an operating system that managed the hardware of the computer. When VMware released its own ESXi, it replaced the Linux kernel with its own kernel. Currently, ESXi supports a variety of guest operating systems, like Debian, Ubuntu, and FreeBSD.

Explain the different components of VMware virtualization and explain how they contribute to the functionality of VMware. (VMware troubleshooting interview)

The following are the different components of VMware’s virtualization:

  • VMware hypervisor: VMware virtualizes physical computers using its core product, the hypervisor. A hypervisor is a layer of software that interacts with the underlying resources of a physical computer, which is called the host, and allocates those resources to other operating systems known as guests. The guest operating system requests resources from the hypervisor. The hypervisor separates every guest OS so it can run without interference from the others. Should one guest operating system suffer a problem like an application crash, become unstable, or become infected with malware, it won’t affect the performance or operation of other operating systems running on the host in any way
  • VMware ESX: VMware’s ESXi data center-focused hypervisor is a type 1, aka “bare metal” hypervisor, which replaces the primary operating system that would interact with a computer’s physical components. It is the successor to ESX, which was a bigger version of the hypervisor that used more of the host computer’s resources. VMware has discontinued ESX since.

How does ESXI compete with other type 1 hypervisors?

VMware’s ESXi competes with several other Type 1 hypervisors in the following ways: 

  • VMware vs. Hyper-V: Microsoft’s Hyper-V is a hypervisor product that allows the user to run multiple operating systems on the same server or client computer. Similar to VMware’s ESXi component, Hyper-V is a Type 1 hypervisor that interacts with the underlying physical computing and memory resources. Hyper-V works differently from ESXi, using partitions to manage its VMs. Hyper-V must run with the Windows operating system. When activated, it installs itself parallelly with the Windows OS on a root partition, which gives Windows exclusive access to the underlying hardware. Eventually, it runs guest operating systems on child partitions that communicate with the physical hardware through the root partition. Hyper-V also ships with Windows 10 clients, competing directly with VMware’s Type 2 Workstation hypervisors.
  • VMware vs. Citrix: Citrix provides application and desktop virtualization products and has a long track record in the virtual desktop integration market. Its main hypervisor offering is the Citrix Hypervisor, known as XenServer, which competes directly with VMware vSphere. Citrix’s range of applications and desktop virtualization products compete with VMware’s Horizon virtual desktop integration product.
  • VMware vs. KVM: Both VMware ESXi and KVM are hypervisors, but KVM is part of the Linux kernel (the core part of the OS). KVM’s huge benefit over VMware ESXi is that it is an open-source product, making its code base transparent. Users can use a variety of open-source virtualization management tools that integrate with the Linux kernel. As with many open-source projects, they may need extra configuration work.

Explain the concept of a VMware workstation.

VMware Workstation has Type 2 hypervisors, which makes it different from a Type 1 hypervisor, which will replace the underlying OS altogether. A Type 2 hypervisor runs as an application on the desktop OS and lets desktop users run a second OS over their main host OS.

VMware Workstation comes in two types or flavors:

  • Workstation Player, which is a free version that supports a single guest OS.
  • Workstation Pro supports multiple guest operating systems and integrates with the virtualization management tools of VMware Enterprise

Explain clustering in VMware. (VMware troubleshooting interview)

Clustering is the process of sharing resources between hosts by grouping them into a cluster and treating them as a single machine. VMware’s clustering technology can be used to pool hardware resources between the hypervisors running on each host in the cluster. When adding a VM to a cluster, users can give it access to those pooled resources. There may be several clusters in a VMware-powered enterprise.

VMware allows users to create and manage clusters within its vSphere environment. A cluster supports many vSphere features, such as workload balancing, high availability, and fault-tolerant resilience. VMware clustering gives users access to several VMware functions to make their virtual infrastructure run smoothly and reliably.

What is VMware HA?

HA stands for high availability. VMware’s vSphere High Availability (HA) solution lets users switch virtual machines between physical hosts if the hardware fails. It supervises the cluster, and if it detects a hardware failure, it restarts its VMs on an alternate host.

VSphere HA usually designates one host in a cluster as the “master,” and the others are called “slaves.” The master communicates with the vCenter Server, reporting back to the slave hosts.

What is VMware DRS? (VMware troubleshooting interview questions and answers)

VMware Distributed Resource Scheduling (DRS) works by balancing workloads between different ESXi hypervisors. Usually, when many VMs are allowed to run unmanaged across the host machines, a lot of trouble ensues. Some VMs will demand more CPU and memory resources than others. This will lead to the creation of unbalanced workloads, with hosts handling more than their share of work while others sit idle. Hence, DRS will solve that issue by blaming the workload between ESXi hypervisors.

Explain the concept of VM fault tolerance. (VMware interview questions)

While vSphere HA provides rapid recovery from outages, users can still expect downtime while it moves and restarts a VM. If users need more protection for mission-critical applications, vSphere Full Tolerance offers a high level of availability. It promises no loss of any data, transactions, or connections.

VSphere Fault Tolerance works by running a primary and secondary VM on separate hosts in the cluster and ensuring that they are identical at any point in the process. If either of their hosts fails, the remaining host continues operating since they are similar, and vSphere Fault Tolerance creates a new secondary VM, which will reestablish redundancy. VSphere automates the entire process.

What is SDDC, and what are the elements of SDDC?

VMware’s plans to virtualize and automate everything in the data center are based on the software-defined data center (SDDC) concept.

The following are VMware’s SDDC elements: 

VMware’s NSX: VMware NSX is a network virtualization product that allows users to define and control their IT network logically in software. Users can consolidate network functions such as switching, routing, traffic load balancing, and firewalls into hypervisors running on computers with x86. Users can manage these functions together from a single screen rather than manually configuring different hardware across different interfaces, and users can also apply software-based policies to automate network functions. VMware’s network component brings the same virtualization benefits to networking, software, and computing functions.

VMware vSAN: VMware vSAN is part of VMware’s storage virtualization solution. It creates a software bridge interface between VMs and physical storage devices. This software represents physical storage devices as a single pool of shared storage, which will be accessible by machines in the same cluster.

Using VMware vSAN, users can use storage on any computer in a cluster rather than relying only on a single computer, which might run out of storage. It additionally avoids wasting a physical computer’s storage if the VMs running on that computer don’t use it. VSAN integrates with vSphere to create a storage pool for managing tasks such as high availability, workload migration, and workload balancing. Custom policies give users full control over how vSphere uses shared storage.

VMware Cloud: VMware offers several products and services under the VMware Cloud banner. VMware Cloud Foundation is an integrated software suite supporting hybrid cloud operations. It includes a range of services for software-defined computing, storage, networking, and security, and it is available as a service from a wide range of cloud providers. 

VMware HCX: VMware HCX is one of the components of the VMware Cloud that helps companies use a mixture of computing environments. This gives IT teams the functionality they want at the right cost and enables them to keep more sensitive data secure on their computers. HCX is a software-as-a-service (SaaS) offering that lets users manage multiple vSphere instances across different environments, ranging from on-premise data centers to hosted cloud environments.

Formerly called Hybrid Cloud Extension and NSX Hybrid Connect, HCX abstracts users’ vSphere environments so that the VMs it manages appear to have the same IP address regardless of where they run. HCX uses an optimized wide-area network (WAN) connection to easily extend on-premise applications to the cloud without reconfiguration. This allows users to call on extra computing power from the cloud to maintain the performance of on-premise applications when computing demand exceeds on-premise physical resources. HCX lets users replicate their data to a cloud-based vSphere instance for disaster recovery.  Learn more about Saas like Vmware and AWS salary in India for freshers here.