Ask the Experts

Ask the Experts

• How can virtualization reduce power consumption?

  Virtualization offers many advantages, including workload portability and dynamic resource provisioning, but how do these translate into power savings?  Continue Reading

• What is SR-IOV and how can it be deployed on a virtualized server?

  SR-IOV allows a single I/O resource to be shared efficiently between multiple virtual machines.  Continue Reading

• What is VMDq and what is needed to deploy it on a virtualized server?

  VMDq allows the creation of parallel queues by moving packet sorting and queues out of the hypervisor's virtual machine manager.  Continue Reading

• How can I tell if a virtual CPU is to blame for poor performance?

  How can I tell if the allocation of multiple virtual CPUs is causing a performance problem on a virtual machine?  Continue Reading

• If one vCPU is good, why wouldn't more be better?

  Is it bad to assign more virtual CPUs to a VM than absolutely needed? Shouldn't another vCPU lead to better performance?  Continue Reading

• How is a physical CPU divided into multiple virtual CPUs?

  How many virtual CPUs can you allocate to a VM, and how does this limit the number of VMs on a server?  Continue Reading

• How does virtualized connectivity help server workload performance?

  I/O virtualization can boost server performance and simplify hardware requirements, while increasing the maximum number of I/O-intensive VMs on a server at the same time.  Continue Reading

• Can you recover data after an unwanted Hyper-V Checkpoint restoration?

  If you mistakenly restore a VM to a previous state, have you forever lost changes that were made after the Checkpoint was created?  Continue Reading

• What flexibility does running Hyper-V on SCVMM 2012 R2 provide?

  Hyper-V offers many features, but when its run on SCVMM 2012 R2, there is more flexibility with what you can do.  Continue Reading

• How do Hyper-V Integration Components affect performance?

  What are Hyper-V Integration Components, and are there any recommendations for boosting virtual machine performance?  Continue Reading

• What happens with Hyper-V checkpoint behind the scenes?

  Hyper-V checkpoints allow admins to create snapshots of running VMs, but what is happening in the background to make this possible?  Continue Reading

• Is a single management tool enough for heterogeneous hypervisor environments?

  When it comes to deciding how to manage a heterogeneous hypervisor environment, it can simply boil down to the price. The makeup of your environment also plays a role in choosing hypervisor management tools.  Continue Reading

• What's the best way to manage a heterogeneous hypervisor environment?

  Managing multiple hypervisors can be a time-consuming challenge. Here are the answers to common concerns when it comes to managing a heterogeneous hypervisor environment.  Continue Reading

• What are the vSphere clustering requirements?

  What are the hardware and software requirements for server clustering with vSphere 5.5?  Continue Reading

• What do I need to create a VMDK file larger than 2 TB?

  What hypervisor and host system are required for VMDK files larger than 2 TB? Are there any potential problems to consider?  Continue Reading

• How do I use SR-IOV for Hyper-V VMs?

  Single Root I/O Virtualization, or SR-IOV, can help reduce latency and increase I/O throughput when enabled for Hyper-V VMs.  Continue Reading

• How do I deploy a library server for SCVMM?

  A library server will allow you to take advantage of SCVMM's features, but there are several factors to keep in mind when creating one.  Continue Reading

• How does moving huge VMDK files affect storage?

  VMware ESXi 5.5 enabled VMDK files larger than 2 TB, but huge VMs bring storage challenges.  Continue Reading

• Why would you need huge virtual disk files?

  As more enterprises look to virtualize top-tier applications, many are seeing a growing need for huge virtual disk files.  Continue Reading

• What are the new security features for VMs in Hyper-V hosts?

  Security will be a hot topic this year. Here are some new security features for Hyper-V virtual machines to keep your environment safe.  Continue Reading

• VSID or VLAN ID for Hyper-V network virtualization?

  Microsoft now offers two options with Hyper-V to isolate VMs on virtual networks. Do you know which option is better for your deployment?  Continue Reading

• What's the best way to configure a storage LUN for VMs?

  There are many factors to consider when configuring a storage LUN to ensure it provides your VMs with the best possible performance.  Continue Reading

• What are the best VM patch management guidelines?

  Every IT pro knows that it's important to install critical patches to virtual machines in a timely manner, but what about the less serious updates?  Continue Reading

• Which storage protocol should I use for VMware vSphere?

  There are several storage protocol options for a VMware vSphere environment. Choosing the best one for your deployment will depend on your resources and performance goals.  Continue Reading

• What's the best way to configure BIOS settings for virtualization?

  There are several BIOS settings you may need to change on your host server to ensure that hypervisors will run correctly.  Continue Reading

• What does N+1 redundancy mean?

  In data centers, N+1 redundancy is used to express the idea that a system should be designed to withstand the loss of a component.  Continue Reading

• How does application containerization compare to Linux Containers?

  Linux Containers have been around for a while, so how is that technology different from application containerization offered by companies like Docker?  Continue Reading

• How is containerization different from virtualization?

  Containers and virtual machines both allow you to abstract the workload from the underlying hardware, but there are important differences in the two approaches that need to be taken into account.  Continue Reading

• What is the maximum supported configuration for Hyper-V VMs?

  When it's time to provision Hyper-V VMs in Windows Server 2012, you need to know the supported maximum configurations.  Continue Reading

• The inner workings of Microsoft Hyper-V Replica

  Hyper-V Replica automates the VM replication process, but there's a lot going on behind the scenes to make this new technology work.  Continue Reading

• Brand name or white box server for virtualization?

  There are no technical reasons to choose a particular brand for your server hardware, but consider the risks before you buy a white box server.  Continue Reading

• The difference between VMware's VSAN and a VSA

  Both virtual storage appliances and VMware's VSAN are software approaches designed to create affordable shared storage, but they are very different.  Continue Reading

• Hardware specs you need in a server for virtualization

  When it’s time to buy a new server, make sure you're getting the CPU and memory you need to maximize consolidation.  Continue Reading

• What to do if a VM won't restart after a host failure

  VMware High Availability is designed to minimize downtime by migrating VMs in the case of a host failure, but what happens when it doesn't work?  Continue Reading

• Troubleshooting a VMware DRS load balancing failure

  VMware's DRS helps organizations better utilize resources and can prevent resource contention, but DRS load balancing doesn't always work as expected.  Continue Reading

• How Storage vMotion works under the hood

  VMware makes moving a VM from one datastore to another simple with Storage vMotion, but the details of how the feature works are more complex.  Continue Reading

• Reducing CPU ready time will get your hungry VMs a seat at the table

  Throwing vCPUs at a slow VM is not the answer to better performance when CPU ready time is high.  Continue Reading

• Network conflict resolution: Changing a virtual machine MAC address

  A virtual machine MAC address is randomly generated, but that doesn't guarantee you won't have duplicates. Find out how to change a VM's MAC address.  Continue Reading

• Not so fast: VMware's NSX has hardware and software requirements

  Before you decide to use VMware's NSX network virtualization platform, be sure you know about its software and hardware requirements.  Continue Reading

• VMware supports a massive VMDK file size, but why create a monster?

  Practical uses for a 64 TB VMDK file are limited today, but as storage needs grow, you might find a reason to embrace monster VMs.  Continue Reading

• Differentiating C-state and P-state in server power management

  C-state and P-state both offer options for managing system power, but they are very different from one another.  Continue Reading

• How vSphere Metro Storage Cluster differs from Site Recovery Manager

  Both vSphere Metro Storage Cluster and VMware Site Recovery Manager will help your organization limit downtime, but they work in very different ways.  Continue Reading

• Local data storage or SAN: How storage location affects VM performance

  Do the performance advantages of local storage outweigh the management benefits of a storage area network?  Continue Reading

• How bad do swap files affect virtual machine performance?

  Modern technology can prevent VMs from grinding to a halt if there's a memory shortage, but using swap files does slow performance. Find out why.  Continue Reading

• Hyper-V 2012 R2 changes: What are Generation 2 virtual machines?

  Hyper-V 2012 R2 includes some important changes virtualization admins should know about, including the addition of Generation 2 VMs.  Continue Reading

• Though OS-independent, thin hypervisors provide solid security

  If you think smaller hypervisors are more vulnerable, think again. A thin hypervisor may be more secure than bare-metal versions.  Continue Reading

• Virtual security tactics for Type 1 and Type 2 hypervisors

  It's no surprise that Type 1 and Type 2 hypervisors require different security considerations, but we asked an expert to clarify.  Continue Reading

• How NPIV almost guarantees unique WWNs

  Though aberrations exist, WWNs are nearly always unique, and the advent of NPIV technology on virtualization platforms helps ensure this fact.  Continue Reading

• What is I/O fencing and how does it work?

  I/O fencing helps prevent file system corruption, but do you know how it works and when to use it?  Continue Reading

• Is there a rule of thumb for how often to create a snapshot?

  Virtual machine snapshots can help organizations avoid lengthy downtime, but do you know when and how often you should create a snapshot?  Continue Reading

• Moving virtual machines from VMware to Hyper-V with SCVMM and MVMC

  Find out how easy it is to make the transition from VMware to Hyper-V with SCVMM or the Microsoft Virtual Machine Converter.  Continue Reading

• Working with the limitations of SAN-based backups and backup tools

  Neither SAN-based VM backups nor VCB can do it all. When you understand the scope of each method, you'll make a better disaster recovery decision.  Continue Reading

• Diagnosing the cause of failed VM snapshots

  You've done everything right -- even quiesced the VM -- but you're still experiencing a snapshot error. What's causing the failure?  Continue Reading

• What are the best backup methods and tools for my VMs?

  Choosing the wrong VM backup methods and tools could cause major problems in your infrastructure. Avoid the headaches by remembering the basics.  Continue Reading

• OVirt vs. RHEV: Are they interchangeable?

  If you wonder about the difference between RHEV 3.1 and oVirt 3.1, you're not alone. We asked an expert to clear up any oVirt vs. RHEV confusion.  Continue Reading

• Should you consider VirtualBox for server virtualization?

  On desktops, VirtualBox offers many core virtualization features, such as OS testing and VM creation. Could it function as a hypervisor alternative?  Continue Reading

• Advantages of storing a VM on an SMB file share

  Changes to Hyper-V and the SMB 3.0 protocol could make using an SMB file share the right decision for your environment.  Continue Reading

• Hyper-V Replica improves fault tolerance without a failover cluster

  Are you looking for a cheaper alternative to a failover cluster? Windows Server 2012 includes a new feature, Hyper-V Replica, that can be an effective substitute.  Continue Reading

• Ask the expert: When to use thin provisioning

  Thin provisioning is an important part of your data center. Our expert explains how it can add flexibility and storage space to an infrastructure.  Continue Reading

• What’s in your virtualization home lab?

  A virtualization home lab is a great way to gain more experience, but it can be pricey. Even so, our advisory board thinks it’s worth the investment.  Continue Reading

• Virtual machine hosts as domain controllers?

  Should a host server be used as a domain controller? Ron Oglesby offers his thoughts in this expert response.  Continue Reading

• Servers for virtualization

  Virtualization expert Andrew Kutz discusses which server is best for hosting virtual machines.  Continue Reading

• Dual-core quad-processor systems, or quad-core dual-processor systems?

  We are looking at hardware for our new ESX farm and are wondering if we should go dual-core quad-processor systems, or quad-core dual-processor systems. Essentially we will have the same number of cores in either case, but the dual-processor servers...  Continue Reading

• What is NPIV and why is it important?

  Storage expert James Geis explains what NPIV is, and how it relates to a virtual storage environment.  Continue Reading

• Best practices for naming VMware virtual machines

  Are you naming your VMware virtual machines in a way that will help you keep track of where they are and what they do? If not, you must read this expert response by Andrew Kutz.  Continue Reading

• Server partitioning and VMware

  Wondering how you should partition your host server for optimal VMware virtualization? Read this expert response by Andrew Kutz to find out.  Continue Reading

• Paravirtualization pros and cons

  Expert Bernard Golden takes a look at the strengths and weaknesses of paravirtualization in this expert response.  Continue Reading

• Does VMware have memory sharing capability?

  VMware is the standard in virtualization, but does it support memory sharing? Site expert Andrew Kutz has the answer in this expert response.  Continue Reading

• Optimizing virtual hard disks with RAID arrays

  After reading one of expert Anil Desai's articles, a reader had some more questions. Find out what our expert had to say about designing a RAID array for placement on multiple VHDs.  Continue Reading

• Hyperthreading in virtualized environments

  If hyperthreading is turned off, will virtual servers still run? Find out from Andrew Kutz in this expert response.  Continue Reading

• What operating systems does Xen support?

  Xen supports a variety of operating systems, and Bernard Golden will touch on all of them in this expert response.  Continue Reading