A lot of corporate data centers are built around VMware’s vSphere product, which is a leader in virtualization software. As a result, IT specialists place a high value on understanding of VMware and its products. These VMware interview questions can aid you in becoming familiar with a variety of issues linked to VMware vSphere if you are getting ready for an interview.
In this article, we’ll give you a list of 50 potential VMware interview questions and responses, with an emphasis on VMware vSphere 8 and its configuration maximums.
1. What is VMware vSphere?
A single physical server can host several virtual machines (VMs) thanks to the virtualization software VMware vSphere. It offers a number of functions, such as the capacity to manage virtual machines, provide resources to virtual machines, and carry out live virtual machine migrations.
2. What are the main components of VMware vSphere?
The ESXi Hypervisor, vCenter Server, and vSphere Client are the three core parts of VMware vSphere.
ESXi Hypervisor: The ESXi Hypervisor is a compact operating system that allows for the development and administration of virtual machines on physical servers.
vCenter Server: You may manage numerous ESXi hosts and virtual machines using vCenter Server, a central administration platform, from a single interface.
vSphere Client: The vSphere Client is a graphical user interface (GUI) that enables you to manage your VMware vSphere environment by connecting to the vCenter Server.
3. What is a virtual machine?
A virtual machine (VM) is a computer that simulates a physical machine using software. As though each operating system and program were running on a separate physical machine, it enables you to run several operating systems and apps on a single physical server.
4. What types of virtualization are there?
Virtualization comes in a variety of forms, including:
Server Virtualization
With this sort of virtualization, several operating systems and applications can operate on the same hardware by generating virtual machines on a single physical server.
Desktop Virtualization
By building virtual desktops that users can access remotely, this kind of virtualization enables users to work from any location and on any device.
Network Virtualization
To divide traffic, isolate applications, and make network management simpler, one sort of virtualization involves building virtual networks.
Storage Virtualization
In order to pool and manage actual storage resources, this sort of virtualization entails the creation of virtual storage devices.
Application Virtualization
This kind of virtualization entails developing virtualized versions of software that may be used on any device without installation.
5. How many different types of hypervisors are there?
There are numerous types of hypervisors, including:
Type 1 (native or bare-metal) hypervisors: These hypervisors operate directly on the physical hardware, enabling the installation and use of different operating systems on the same physical server. Microsoft Hyper-V, Xen, and VMware ESXi are a few examples of Type 1 hypervisors.
Type 2 (hosted) hypervisors: By running on top of a host operating system, these hypervisors enable the creation and operation of several virtual machines on the same physical server. Oracle VirtualBox, Parallels Desktop, and VMware Workstation are a few examples of Type 2 hypervisors.
There could be two other hypervisors:
Container-based hypervisors: These hypervisors use container technology to allow multiple applications to run on the same physical server while still providing isolation between them. Container-based hypervisors include Docker and Kubernetes.
Cloud hypervisors: These hypervisors are used to create and manage virtual machines in a cloud computing environment. Cloud hypervisors include Amazon EC2, Microsoft Azure, and Google Cloud Compute.
6. What is the VMware vCenter Server’s purpose?
vCenter Server is VMware vSphere’s central management platform. It manages multiple ESXi hosts and virtual machines from a single interface and includes features such as clustering, resource pooling, monitoring, and automation.
7. What is the difference between vSphere and vCenter Server?
While vCenter Server serves as VMware vSphere’s primary administration platform, vSphere is a virtualization technology that enables you to host many virtual machines on a single physical server. The virtualization infrastructure is provided by vSphere, and the management and configuration of vSphere environments is handled through a centralized interface by vCenter Server.
8. What is the VMware vCenter Enhanced Linked Mode, and how does it operate?
The VMware vCenter Enhanced Linked Mode feature enables you to control multiple vCenter Servers and the vSphere environments they are connected to from a single interface. It is simpler to carry out operations like VM migration or resource management across many environments when you use Enhanced Linked Mode, which enables you to view and control all of your vSphere environments as though they were a single entity.
You need at least two vCenter Servers linked to the same single sign-on (SSO) domain in order to use enhanced linked mode. Once linked, you may view and control all of the vCenter Servers and the vSphere environments they are connected to using a single interface by using the vCenter client.
Also, with Enhanced Linked Mode, you can view and control the resources and inventory of numerous vCenter Servers from a single location, which makes it simpler to complete activities like:
- Migrating VMs between vCenter Servers
- Viewing and managing resource utilization across multiple vSphere environments
- Creating and managing alarms and events for multiple vCenter Servers
- Performing searches across multiple vCenter Servers
Overall, Enhanced Linked Mode might be a helpful tool for streamlining the management of big and complicated vSphere installations.
9. What is a virtual machine template?
A pre-configured virtual machine that may be used as a springboard for building new VMs is known as a virtual machine template. By giving new VMs a dependable starting configuration, templates help speed up operations and lower mistake rates.
10. Why are virtual machines used instead of the original hardware in some cases?
There are several reasons why virtual machines are used instead of the original hardware in some cases:
Cost savings
By allowing numerous VMs to run on a single physical server, virtualization can assist cut hardware expenses by eliminating the need for additional physical servers.
Resource utilization
By enabling many VMs to share the same hardware resources, virtualization can assist increase resource utilization by maximizing the usage of hardware resources.
Flexibility
Scaling up or down as needed is simpler with virtualization because VMs can be simply created, removed, or relocated between physical servers.
Compatibility
Applications that might not be compatible with a certain hardware configuration can now be run more easily thanks to virtualization, which enables VMs to run on a variety of hardware platforms.
Disaster recovery
In the event of a hardware failure, virtualization enables speedy VM restoration or VM relocation, which can aid in disaster recovery.
11. What is a resource pool?
A logical collection of resources, including as CPU, memory, and storage, that may be assigned to virtual machines is known as a resource pool. Resource pools can be used to prioritize resources for various VMs or workloads and enable flexible, granular resource allocation to VMs.
12. What is a vApp?
A virtual application (vApp) is a container that can house one or more virtual machines together with any necessary networks and storage. With the help of vApps, you can bundle and distribute complicated application environments as a single unit, simplifying management and environment migration.
13. What is VMware vMotion?
A feature of VMware vSphere called VMware vMotion enables you to move running virtual machines between physical hosts while they’re still running, with no downtime required. Due to the fact that it enables you to relocate VMs to various hosts without impairing the service they offer, this can be helpful for maintenance or load balancing purposes.
14. What is VMware DRS?
A feature of VMware vSphere called VMware Distributed Resource Scheduler (DRS) automates the placement and allocation of resources to virtual machines (VMs) in accordance with pre-established policies. DRS can assist in ensuring that virtual machines (VMs) obtain the resources necessary for maximum performance as well as in balancing workloads across many hosts to maximize resource efficiency.
15. What is VMware HA?
Automatic failover protection for virtual machines is offered by VMware High Availability (HA), a component of VMware vSphere. In the event of a host failure, HA will promptly restart the impacted VMs on other hosts in the cluster, minimizing downtime and assuring the continued availability of your applications.
16. What is a Cluster in VMware vSphere?
In VMware vSphere, a cluster is a collection of hosts that are controlled collectively. Clusters enable resource sharing, high availability, and load balancing for virtual machines.
17. What is a Host in VMware vSphere?
A host in VMware vSphere is a physical server that is running the ESXi hypervisor and is managed by the vCenter Server. Hosts provide the physical resources (such as CPU, memory, and storage) that are used by the VMs running on them.
18. What is a datastore in VMware vSphere?
In VMware vSphere, a datastore is a logical container used to store virtual machine files and other types of data. Virtual machine disks, templates, and other items can be kept in datastores, which can be found on local storage, shared storage, or external storage.
19. Explain iSCSI storage
The storage protocol known as iSCSI (Internet Small Computer System Interface) enables a computer to access and control storage devices over a network. Storage devices are made simple to connect to and utilize across a network using iSCSI, which uses common Ethernet networks and TCP/IP protocols to send data between the computer and the storage device.
SANs, which allow numerous computers to access and use the same storage devices, are shared storage environments that are frequently built using iSCSI. Virtual machines (VMs) can access shared storage resources over a network when storage devices are connected to virtualization environments using iSCSI.
One of the main benefits of iSCSI is that it makes it simple to connect to and use storage resources remotely by enabling access to and management of storage devices over a network.
20. Explain NFS and VMFS
NFS
A computer can access files over a network by using the NFS (Network File System) network file system protocol. It’s simple to share data between computers thanks to NFS, which enables a client to mount a distant file system and access it just like a local file system. File locking is supported by NFS, which scales to larger storage configurations and enables concurrent access and modification by multiple clients.
VMFS
In a vSphere environment, virtual machine files and other data are kept in a proprietary file system called VMFS (Virtual Machine File System). VMFS offers file locking at the block level, enabling many VMs to access and alter files at the same time, and it enables multiple ESXi hosts to access and share the same datastore. Because to its block-level locking and other design advantages, VMFS is typically quicker than NFS, but it can only support up to 64 TB per datastore.
21. What are the cold and hot migrations?
The process of moving a virtual machine (VM) from one physical host to another is referred to as cold migrations and hot migrations. The primary distinction between the two is whether the VM is turned off during the migration process or kept running.
Cold migration: A cold migration involves turning off the virtual machine (VM) before migrating it to a new physical host. When there is no requirement to maintain the VM running throughout the migrating process or for maintenance chores, cold migrations are commonly used. By utilizing vSphere technologies like vMotion or Storage vMotion, cold migrations can be carried out.
Hot migration: A hot migration includes relocating an active virtual machine to a different physical host. Hot migrations, which may be carried out using vSphere technologies like DRS or vSphere HA, are frequently used to transfer virtual machines (VMs) across hosts in a cluster or to carry out load balancing. Hot migrations may cause the VM some disruption because there may be a small period of downtime while the migration is being made.
22. What is a Virtual Switch in VMware vSphere?
In VMware vSphere, a virtual switch is a software-based networking element that enables communication between virtual machines and with the physical network. Virtual switches can be set up with a number of networking characteristics, including traffic shaping, VLAN tagging, and security policies.
23. What is a port group in VMware vSphere?
In VMware vSphere, a port group is a logical collection of network ports on a virtual switch. Port groups can be used to divide network traffic and apply various networking rules to various collections of virtual machines.
24. What is a vSphere Standard Switch?
A single ESXi host is used to generate and administer a virtual switch known as a vSphere Standard Switch (vSS). Conventional switches have less complexity and weight than distributed switches but less centralized administration and scalability.
25. What is a distributed switch in VMware vSphere?
In VMware vSphere, a distributed switch (vDS) is a virtual switch that spans many hosts and enables communication between virtual machines (VMs) running on those hosts and the physical network. Distributed switches make it easier to manage massive and intricate vSphere setups by offering a centralized administration interface for virtual networking.
26. What is vSphere Replication?
A feature of VMware vSphere called vSphere Replication lets you duplicate virtual machines between several vSphere environments, either inside the same data center or among other data centers. Both catastrophe recovery and moving virtual machines between environments are possible with vSphere Replication.
27. What is vSphere Update Manager?
Patch and update management for vSphere environments is handled by vSphere Update Manager. It lets you locate and apply upgrades to ESXi hosts, virtual appliances, and other vSphere environment components.
28. What is vSphere Lifecycle Manager (vLCM) and in which version of VMware vSphere it was introduced?
A feature of VMware vSphere called vSphere Lifecycle Management (vLCM) allows you to automate and manage the lifespan of your vSphere infrastructure. This includes managing the ESXi versions, updates, and drivers as well as the VM Hardware and VMware Tools versions on VMs in your vCenter. It enables you to quickly deploy, update, and maintain your vSphere environment, ensuring that every vSphere component is configured consistently and is current.
29. What is a virtual machine snapshot in VMware vSphere?
An exact replica of a virtual machine’s disk and memory state is called a virtual machine snapshot in VMware vSphere. The state of a virtual machine (VM) can be preserved using snapshots before changes are made, or several copies of a VM can be made for testing or development.
30. What is a virtual machine clone in VMware vSphere?
In VMware vSphere, a virtual machine clone is a replica of an existing virtual machine made with the “Clone” feature of the vCenter Server. For testing or development reasons, clones make several copies of a virtual machine very quickly.
31. What is a content library in VMware vSphere?
A content library is a centralized repository for vApps, virtual machine templates, and other information that may be used to install and manage virtual machines in VMware vSphere. Several vSphere environments can use content libraries to store and distribute templates and other types of material.
32. What is vSphere Storage DRS?
A component of VMware vSphere called vSphere Storage DRS enables you to automatically distribute workloads among various storage devices in accordance with pre-established policies. Storage DRS can help by spreading workloads equitably across various storage devices, ensuring that virtual machines (VMs) have access to the storage resources they require. Storage DRS can also aid by improving resource consumption.
33. What is vSphere Storage I/O Control?
vSphere Storage I/O Control (SIOC) is a feature that lets you prioritize and distribute storage I/O resources to various virtual machines (VMs) or workloads. Storage I/O Control is a tool that may be used to guarantee that crucial virtual machines (VMs) have access to the storage resources they require while also enabling equitable resource sharing among several virtual machines (VMs).
34. What are vSphere Storage Policies?
Your virtual machines’ storage needs are determined by VMware storage policies (VMs). Because they control how storage is distributed to the VMs, these policies ensure the necessary level of service. One or more VM storage policies are assigned to every deployed VM to a vSAN datastore.
35. What is vSphere Fault Tolerance?
A component of VMware vSphere called vSphere Fault Tolerance (FT) creates a live backup copy of the virtual machine that can take over if the parent VM fails, ensuring continuous availability for virtual machines. Mission-critical workloads can be shielded against downtime brought on by hardware or software issues with vSphere FT.
36. What is Fault Tolerant Logging?
Fault Tolerance (FT) logging is the name for the communication that takes place when two ESXi hosts are configured to work together. It is important to configure a VMkernel port before configuring FT between two hosts.
37. What happened if the vCenter Server goes down with Fault Tolerance configuration?
vCenter Server is only needed to enable Fault Tolerance (FT) on a virtual machine (VM). After FT is configured, vCenter is not required to be online for FT to function. In the event of a failure, FT failover between the primary and secondary VMs will occur even if vCenter is down.
38. What is vSphere Encryption?
vSphere Encryption is a VMware vSphere feature that allows you to encrypt virtual machine disks and other at-rest data. vSphere Encryption can be used to protect sensitive data from unauthorized access and to help meet data security compliance requirements.
39. What is vSphere Content-Based Read Cache (CBRC)?
The vSphere Content-Based Read Cache (CBRC) feature allows you to cache frequently accessed virtual machine data in memory to improve read performance. CBRC can be used to speed up workloads that rely heavily on read operations, such as databases or web servers.
40. What are vSphere Host Profiles?
vSphere Host Profiles is a VMware vSphere feature that allows you to create and manage ESXi host configuration profiles. Host profiles can be used to enforce consistent configurations across multiple hosts and to automate host deployment and configuration.
41. What is vSphere Quick Boot?
vSphere Quick Boot is a VMware vSphere feature that allows you to restart an ESXi host quickly without requiring a full hardware reboot. Quick Boot can be used to apply patches or updates to ESXi hosts while keeping the VMs running on those hosts operational.
42. What is vSphere Metro Storage Cluster?
A VMware vSphere Metro Storage Cluster configuration is a vSphere-certified solution that combines replication with array-based clustering. These solutions are typically deployed in environments where the distance between data centers is limited, such as metropolitan or campus environments.
43. What are vSphere Big Data Extensions (BDE)?
vSphere Big Data Extensions (BDE) is a software product that allows users to deploy and manage Apache Hadoop and Apache Spark workloads on top of VMware vSphere, a virtualization platform that allows users to build and run virtual machines. BDE integrates with the vSphere infrastructure, allowing users to run big data workloads while leveraging vSphere’s scalability, security, and resource management capabilities.
44. What is vSphere with Kubernetes?
vSphere with Kubernetes is a VMware vSphere feature that allows you to run and manage containerized applications on vSphere using the Kubernetes orchestration platform. vSphere with Kubernetes enables the deployment and management of containerized applications in a vSphere environment, as well as integration with vSphere features.
It enables users to run containerized workloads on vSphere while also benefiting from the scalability, security, and resource management capabilities of Kubernetes, an open-source container orchestration platform.
45. What are the maximums for the vSphere 8 configuration?
The maximum vSphere 8 configurations may differ depending on the vSphere edition and hardware used. Among the key maximums for vSphere 8 are:
- Virtual CPUs per virtual machine (Virtual SMP): 768
- Virtual CPUs per host: 4096
- Virtual Disks per Host: 2048
- RAM per virtual machine: 24 TB
- Virtual NICs per virtual machine: 10
- Logical CPUs per host: 896
- Virtual machines per host: 1024
- Virtual disk size: 62 TB
- Hosts per vCenter Server: 2500
- Linked vCenter Servers: 15
- Maximum number of virtual machine storage policies: 1024
- Video memory per virtual machine: 4 GB
- vSAN disk groups per host: 5
- Virtual Machines per cluster: 8000
- Number of vSAN hosts in a cluster: 64
- Distributed switches per host: 16
- Distributed switches per vCenter: 18
46. What is the virtual machine hardware version for VMware vSphere 8?
The virtual machine hardware version for VMware vSphere 8 is version 20.
47. What are the minimum system requirements for vSphere 8?
The minimum system requirements for vSphere 8 vary depending on the vSphere edition and hardware used. Some of the key requirements include:
- Processor: multi-core of 64-bit x86 processors
- Memory: 12 GB RAM
- Storage: 32 GB of persistent storage such as HDD, SSD, or NVMe
- Network: 1 GbE network adapter
48. What are the supported operating systems for vSphere 8?
Many operating systems, including many versions of Windows, Linux, and other Unix-based systems, are supported by vSphere 8. Some of the specific operating systems that are supported by vSphere 8 include:
- Windows Server 2012/2012 R2/2016/2019/2022
- Windows 8.1/10/11
- Red Hat Enterprise Linux (RHEL) 6/7/8/9.x
- CentOS 7.x and later
- Ubuntu 16.04 LTS and later
- SUSE Linux Enterprise Server (SLES) 12 and later
49. What are the supported storage protocols for vSphere 8?
vSphere 8 supports a variety of storage protocols, including:
- Fibre Channel (FC)
- Internet Small Computer System Interface (iSCSI)
- Network File System (NFS)
- vSAN (virtual SAN)
- NVMe Storage
50. What is the licensing model for vSphere 8?
vSphere 8 uses four editions, vSphere Essential Kit, vSphere Essential Plus Kit, vSphere Standard, and vSphere Enterprise Plus, which are licensed per CPU, but since the beginning of 2020, only up to 32 cores are covered. Processors with more cores require the purchase of additional licenses.
Wrapping Up
To summarize, VMware vSphere is a powerful virtualization platform that is widely used in enterprise environments to manage and deploy virtual machines. Understanding the various features and capabilities of vSphere is essential for anyone working with or supporting vSphere environments.
The 50 VMware interview questions and answers outlined in this article are a good starting point for anyone preparing for a vSphere-related job interview and should help you understand the key concepts and technologies involved in vSphere. Whether you are new to vSphere or have been working with it for some time, reviewing these questions and their answers can help you improve your knowledge and skills in this important area of technology.