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VMware Presents a Technical Demo on What’s New with vCloud Air Disaster Recovery

Every company should have a simple, cost-effective, and flexible disaster recovery solution to protect their data in the event of a disaster or disruptive event.

It’s time to consider the cloud with VMware vCloud® AirTM Disaster Recovery.

vCloud Air Disaster Recovery provides a warm-standby virtual data center, requires zero changes to your existing vSphere environment, and supports the systems and applications you run today—without conversions.

We welcome you to join us on March 24, 2015 at 11:00 am PST for a free webcast where our featured speakers will demonstrate how to develop and improve a disaster recovery plan for your organization using VMware vCloud® AirTM. This webcast will walk viewers through the latest enhanced service capabilities, including native failback support, multiple recovery points, and self-service automation.

After this webcast, you will have the skills to:

  • Configure replication
  • Initiate a test failover and failback to restore operations after an outage
  • Self-service automation for defining a recovery playbook
  • View the inventory of snapshots to select from during the time of a failover for a VM

Mark your calendar, and register for the webcast here!

Webcast Details:

  • Tuesday, March 24, 2015
  • 11:00am PST

Featured Speakers:

  • Nicole Kim, Product Line Marketing Manager, VMware
  • David Hill, Senior Technical Marketing Architect, VMware

Ready to get started with the vCloud Air Disaster Recovery? Visit vCloud.VMware.com.

For future updates, follow us on Twitter and Facebook at @VMwareSMB and Facebook.com/VMwareSMB.

Upgrading Your Virtual Environment? Two Options to Consider

Vladan HeadshotPost by vExpert Vladan Seget

Expanding your virtual environment doesn’t always mean growing it in size with more VMs and more hosts. Expansion can also mean upgrading your environment from a previous release – a common fear for many users. This may be a fear of the unknown – the fear that something will break during the upgrade process and leave you with nothing, or the fear of having to adjust to a new environment. Many users (including myself) will choose to stay on an old environment until there is a hardware refresh cycle planned, because it’s often easier to plan the installation of a new environment instead of upgrading old hardware.

When a major upgrade of your virtual environment has been released, usually there are many questions you need to consider. I usually check compatibility with my existing environment and research whether other bloggers or the larger VMware vSphere community have reported any issues with the upgrade.

I also do a few installs and simulate the upgrade on non-production servers, just to see how it goes. If the upgrade involves a much older previous release (like vSphere 4.0 or 4.1), then usually the best approach is to do a fresh install on new hardware (as the old one won’t get much support from the vendor either).

It’s not simple, and sometimes the decision on which is the right approach can be hard to determine. If you’re thinking about upgrading your virtual environment, proper planning and thinking ahead is crucial. Below, I weigh the advantages and disadvantages to upgrading your environment through a fresh install (then moving workloads there) or through an existing environment (in-place upgrade of an existing virtual environment).

Two Ways to Upgrade

  1. Fresh Install – Installation on new hardware
  2. Upgrade existing environment – upgrade of existing virtual infrastructure on the same hardware

Fresh Install on New Hardware:

Advantages:

  • Nice and clean – With a fresh installation (vCenter server, ESXi hosts), you can enjoy a clean environment, without potential misconfigurations from the old environment.
  • Proper testing – With a fresh install, you have time to test if everything works and stress the environment with test VMs.

Disadvantages:

  • It takes more time – As with all things, it takes time to create something from scratch vs. refreshing something that already exists as a framework.
  • New hardware needs new configurations – New networking, new storage, and you also need to activate any functions you have licensed for (vMotion, HA, FT, sVMotion…)
  • You need enough hardware – Usually when upgrading from very old infrastructure, this isn’t as much a problem, as there is usually a hardware refresh planned.
  • New version of your current backup product – New major releases usually bring features that need a backup product to be upgraded first.

vCenter upgrade paths illustration photo (source: VMware blog) where different versions of vCenter servers are as a starting point.

vCenter Upgrade Path

Upgrade Existing Environment on the Same Hardware

Before you hit the upgrade button, you should think twice. Imagine that you migrated to very new environment, but your backup vendor can’t assure backup protection for now because the environment isn’t supported yet. Hey, you should have thought about it earlier, no?

One of your first considerations when upgrading should be your backups and restoration – you’ll need to think of every single scenario for backup/restoration or replication.

Advantages:

  • You keep the same configurations – vCenter is the main piece in the puzzle. It’s on top of the pyramid. By keeping the existing network configuration for vCenter, you can save yourself hours of reconfiguring all the services which rely on vCenter (backup/replication, monitoring products…). Nothing changes on your ESXi hosts.
  • No need for new hardware – It’s a software refresh, which means it can be faster to upgrade. If the hardware isn’t too old, it’s the way to go. Taking precautions, backing up configurations, etc, can mitigate the risk of something going wrong.

Disadvantages:

  • In the event your existing hardware isn’t supported – If your hardware isn’t on the HCL (VMware hardware compatibility list), whether your upgrade will be successful or not is uncertain, due to unsupported NICs, Chipsets, etc..
  • Lack of product support could require you to wait to upgrade  - Sometimes it can take 6 months or more for your backup product to be supported on a new platform, which can lead to upgrade delays.
  • The in-place upgrade of vCenter and ESX hosts – You’ll have to prepare a plan B for each scenario. You should be able to revert back in case something goes wrong. If the host upgrade triggers PSOD or blue screen, are you sure you can revert back? Unreachable vCenter – how will you revert back? For vCenter server VM, it’s necessary to plan a full backup before the upgrade. For ESXi upgrade, you can just backup the configuration through the CLI (command line interface).

Additional Questions Concerning Existing Backup/Replication Solutions:

Existing backup/replication solutions must be certified by the vendor on the new vSphere release before upgrading. A few of the questions that might arise:

Do you plan on having all of your VMs backed up by your existing backup solution? If not, then you’ll need to look for an update/replacement.

How about replication? If you have a remote site where you replicate with a certain product and it’s part of your DR plan, can you confirm that your existing solution is supported in the new vSphere release? This is important to know!

Will you be able to restore a file from few years back with new backup solution? Yes some files/e-mails shall be kept for archiving for legal purposes and for this the backup solutions are configured with Grandfather – Father – Son (GFS) backup scheme to keep older files for archiving purposes.

Note:

Grandfather-father-son backup refers to a common rotation scheme for backup media. In this scheme there are three or more backup cycles, such as daily, weekly and monthly. The daily backups are rotated on a daily basis using a First-in first-out (FIFO) system.. The weekly backups are similarly rotated on a weekly basis, and the monthly backup on a monthly basis. In addition, quarterly, half-yearly, and/or annual backups could also be separately retained. Additional off-site protection can be used and some of these backups are removed from the site for safekeeping and disaster recovery purposes.

Will you be able to restore if something goes wrong with the upgrade process? Imagine that after you upgrade your vCenter VM, you can’t connect back to vCenter. This might mean you don’t have access to the backup server (it’s a VM).  Sure, you can probably connect to a single host, register the backup server VM there and launch a restore of the vCenter VM, but make sure that this is a supported scenario! Check with your backup vendor first.

Mixed Upgrade Approach – The Best of Both Worlds

Let’s consider a mixed approach where you use newly installed infrastructure managed by a new vCenter server for test VMs or for VMs that are “not-so-important.” You could test the performance, reliability, backup/replication, and at the same time, the older vSphere release would continue to function as before. So basically you’ll keep both environments – old hardware with older vSphere version and new hardware installed with latest release.

Advantages:

  • Security – You know the new vSphere release works well on this new hardware (it’s on the HCL). The existing environment running on old hardware has proven to be resilient and reliable. No need to change it. Then you can start migrating the workloads with test and dev VMs.
  • No Service Disruption: The transition phase can take a few months/years, but no need to rush, as the test VMs don’t need a proper backup solution yet, and in a few months, your backup vendor will release an upgrade of the backup product you’re using.
  • No Downtime: The existing environment that hosts business critical applications can maintain its specific configuration/requirements and stay backed up with your current backup solution (and might stay this way until the end of the software support).

Disadvantages:

  • More complexity – Adding another environment to your organization means another layer of complexity and “another single pane of glass”. But if the new environment is considered as a test and dev environment first, then it can turn into an advantage for you and your IT team, especially if your existing environment is running out of capacity. You can use the new environment for test and dev purposes first, then later to move production workloads there.

So this mixed approach in my opinion is the best and most secure, but adds an additional complexity to the environment.

Shared Storage Considerations

Upgrades and major version changes also means changes to your storage architecture. Shifting to a new storage platform like VMware Virtual SAN can directly influence your decision to take the mixed approach. You’ll most likely keep the old infrastructure hooked to your existing SAN and build a new environment based on VMware Virtual SAN.

By upgrading your existing vCenter server, you can also build a new cluster based on VMware Virtual SAN and keep your existing cluster as is with current ESX hosts – a single environment with two different clusters.

Final Thoughts

The upgrade process of any virtual infrastructure (even a very small one) is a complex process and needs to be considered carefully. Define your business priorities like uptime, security and application performance at the outset. Planning ahead can make all the difference between a successful or failed upgrade. .

Before you upgrade your system, visit the VMware Education page for vSphere 6 training and certification.

Learning with VMware Hands-on Labs

Post by vExpert Brian Suhr

Brian SuhrA big challenge for IT staff in the SMB market is learning new technology and keeping their skills current. There can be limited budgets and lack of time available for training. Admins have different training options – but what resources provide the most value for your time and money?

The need to keep your technology skills updated has never been greater than it has been in recent years. IT departments are being asked to implement modern solutions at break neck speed or lose their customers to public cloud services. To stay relevant, the list of skills that need to be learned range from End-User Computing (EUC), cloud management, network and modern infrastructure technologies. A typical SMB IT staff would not have the chance to learn these technologies unless they purchased the technology and learned while they implemented the solution.

This places strain on the staff by forcing them to evaluate solutions and make buying decisions without possessing the needed skillsets. The good news is that the VMware Hands-on Labs (HOL) is a destination that IT people can use to learn new IT skills. The HOL offers different lab modules for a wide variety of VMware products today. These modules range from installation and troubleshooting to just working with the product to see how it might be used for a project.

 

HOL

 

Core Virtualization

For many, the fundamentals of virtualization can still be a challenge as they seek to raise the level of their skillsets. Others may seek to learn new ways to monitor and report on their environments. These are all common and great goals to IT teams, no matter the size of your organization.

The following labs will help you learn a variety of skills:

  • HOL-SDC-1401 – This lab is focused on vRealize Operations and will help students understand how they can better manage their virtual infrastructure. The lab demonstrates how to monitor physical and virtual infrastructure, manage capacity information, monitor applications and build custom dashboards.
  • HOL-SDC-1402 – This lab is focused on the vSphere Distributed Switch. You will learn how the advanced features of VDS can be used to simplify and improve your virtual networking environment.
  • HOL-SDC-1404 – A personal favorite of mine is the vSphere Performance Optimization lab. I think that this should be mandatory learning for every VMware admin. This lab will help you gain a deeper understanding of the things that can affect the performance of your vSphere environment.
  • HOL-SDC-1410 – The Virtualization 101 lab is a good place to start building your foundation. The lab will build your knowledge around vCenter and vSphere.

Cloud Management

There is a lot of discussion about cloud in the SMB market. Business leaders are looking for ways that they can use cloud resources and services. To better prepare for these discussions, the Hands-on Labs provide a wide range of cloud-related lab content.

There are several of labs that fall under this category. I have listed a few below that I would recommend to start:

  • HOL-SDC-1406 – If you are wondering what vCloud Suite is all about, this lab will help answer your questions. You will learn about the products included in the suite and what function each plays in the software defined data center.
  • HOL-SDC-1408 – Software defined storage is big topic recently and VMware VSAN is something many customers are looking to learn more about. This lab helps jump start this process through educating students on the install, operations, monitoring and troubleshooting.
  • HOL-SDC-1481 – The vCloud Air lab helps jump start admins on understanding the VMware hybrid cloud offering. The modules explain consumption models, vCloud Air networking, management and how to deploy new workloads.

End-User Computing

The End-User Computing (EUC) technology space is very much in demand these days. Your end users are asking to access data in new ways and from a range of devices. You might be confused by how to accomplish some of these requests without compromising the security of your business.

These EUC-focused labs will help you get started:

  • HOL-MBL-1451 – This lab is a great place to start when learning what Horizon 6 with View can offer. There have been a lot of updates to Horizon 6 and whether you are a View veteran or a newcomer, you will get a lot of value in this lab. The lab will educate on virtual desktops, application presentation and shared desktops.
  • HOL-MBL-1453 – The workspace portal is covered in this lab. Learn how to provide a centralized point of access and authentication for applications and desktops.

In closing,  VMware has built an impressive set of Hands-on Labs learning content that is available for free. Each lab can offer hours of learning and will help people of all levels. There is a much larger list than just the small amount of labs that I have highlighted in this article, so to try out VMware’s Hands-on Labs, click here.

Follow VMware SMB on FacebookTwitterSpiceworks and Google+ for more blog posts, conversation with your peers, and additional insights on IT issues facing small to midmarket businesses.

Pop Quiz: Take the DR Challenge for a Chance to Win a Pass to VMworld 2015!

Have you mastered your organization’s disaster recovery plan? Think you know the answers to, “When did we last test our plan?” or “How much would an hour of downtime cost?” If so, we want to give you a chance to put your knowledge to the test.

Last year, we launched the first DR Challenge and invited our audience to test their disaster recovery know-how. The participation was so great we’ve decided to bring it back! Sign up for this year’s DR Challenge and try your hand at three quizzes designed to test your mastery of cloud-based disaster recovery facts. A perfect score enters you into a drawing for a free pass to VMworld 2015!

The challenge begins February 12th, and runs through March 25th.  You’ll have roughly 2 weeks to take each quiz. Register now to get started:

Quiz Challenge 1: Feb. 12 – Feb. 25   

Quiz Challenge 2: Feb. 26 – Mar. 11

Quiz Challenge 3: Mar. 12 – Mar. 25

You’re free to take the quiz as many times as you want, but you only need to ace it once to be entered to win the grand prize. (We have faith you can do it, but just in case, we’ll also offer hints along the way.)

Click here to sign up for the DR Challenge. We’ll announce the winners at the end of each challenge, so stay tuned on our social channels. Good luck, everyone!

To learn more about vCloud Air Disaster Recovery, visit us at vCloud.VMware.com.

Could You Get More Bang for Your Virtualization Buck?

Many small and midsize businesses are putting virtualization to work to consolidate servers, cut costs, and increase IT agility. That’s all wonderful news, of course, but the story doesn’t stop there. Now it’s time to ask yourself if you could get even more value from your virtualization investments.

This topic is explored in a new VMware white paper that highlights five ways to take your virtualization environment to a new level. This quick-to-read paper draws on key findings from a recent Management Insight study that found the addition of robust management capabilities can drive 20 to 40 percent gains in key performance metrics for a virtualization environment.

In more specific terms, the paper explores the gains made by adding management capabilities to your VMware vSphere® environment, putting your organization on the path to five quantifiable business benefits: improved capacity utilization, cost savings, strong ROI, business continuity, and greater efficiencies.

The bottom line? When you add robust management capabilities to a vSphere environment with VMware vSphere® with Operations Management™, you reap not just the advantages of the world’s leading virtualization platform but also a wide range of compelling business benefits.

 

 

For a fuller look at this story, check out our new white paper, Five Reasons to Take Your Virtualization Environment to a New Level.

 

 

 

 

 

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Want to Be a Star? Try Virtualizing Your Business-Critical Applications

The virtualization of business-critical applications is not a new trend. VMware customer surveys show that many IT departments are virtualizing more than half of their main business-critical applications—such as Microsoft Exchange, Oracle, and SAP. [i]

The reasons for virtualizing business-critical apps are pretty straight forward: reduce risk and improve service levels, reduce cost and complexity, improve manageability, and strengthen security and compliance.

Here’s where things get even better. When you take the lead in initiatives that yield benefits like these, you could put yourself on the path to a promotion, and maybe even one of those coveted corner offices. It all adds up to a win for the business and a win for your IT organization—and the IT practitioners who make it happen.

So how do you get started on a virtualization initiative? That question is addressed in a new VMware eBook that offers tips on best practices for virtualization projects, along with tangible examples of the gains you can achieve when you virtualize applications like Microsoft SQL Server, Microsoft Exchange, and SAP.

One important tip from this paper: Virtualizing business-critical applications is a team sport. That team should comprise all key stakeholders, including application end users and the owners of the systems that will be virtualized. The eBook notes: “By having involvement by the end users and following a methodical process, you will increase the chances of success and recognition after the project goes live.”

And what could that recognition bring? “By virtualizing business-critical applications, and doing it in a way that reduces risk, improves service levels, and reduces costs, you are able to deliver tangible business benefits to the organization. These types of results could potentially result in more exciting projects and promotion opportunities for you, the IT practitioner.”

 

 

For the full story, read the eBook Why Virtualizing Your Business-Critical Applications Can Lead to a Promotion.”

 

 

 


[i] Source: VMware customer survey, January 2010, June 2011, March 2012, and June 2013.

 

Follow VMware SMB on FacebookTwitterSpiceworks and Google+ for more blog posts, conversation with your peers, and additional insights on IT issues facing small to midmarket businesses.

Calling all SMBs: With new vSphere 6, you can run one cloud for any application

The one cloud, any application vision is now real with a host of new features and functionality being introduced today with the release of vSphere 6.  This is particularly great news for SMBs looking to further streamline and simplify their IT environment and maximize their virtualization investment.

There are two key product announcements that are particularly relevant for SMBs:

  • vSphere 6: provides new vMotion capabilities for long-distance live migration with zero downtime, as well as multi-processor fault tolerance to deliver continuous availability for VMs up to four CPUs.
  • Virtual SAN 6: now delivering an all-flash architecture for both caching and data persistence.  With Virtual SAN 6, SMBs can take advantage of their storage resources in their servers to further bring down hardware costs, while at the same time simplify your overall IT operations.

To learn more about how your SMB can run one cloud for any application, as well as additional information about the launch announcements, read the full announcement on our company blog, Tribal Knowledge, or see the announcement from our CEO, Pat Gelsinger, on our microsite.

Follow VMware SMB on FacebookTwitterSpiceworks and Google+ for more blog posts, conversation with your peers, and additional insights on IT issues facing small to midmarket businesses.

Taking virtualization to the next level

The mobile-cloud era has cast a new reality upon IT services. With more users are operating from more endpoints and moving more data, business expects increasingly more capabilities from IT—often more than a resource-strapped IT organization can rightly deliver.

Bridging this “expectations gap” calls for a different approach to managing IT. We believe the VMware Software-Defined Data Center provides you with that approach.

Perhaps you’ve already embraced a virtualization platform such as vSphere to consolidate your servers and pack more computing power into less space. But the Software-Defined Data Center takes you beyond the benefits of vSphere; with the Software-Defined Data Center you can also virtualize networking and storage while you apply intelligent management to your entire infrastructure.

What is the Software-Defined Data Center? It’s a highly automated, easily managed platform that embraces all applications, providing fast deployment across data centers, clouds, and mobile devices. And to help you establish a Software-Defined Data Center, VMware has introduced VMware® vSphere with Operations Management™.

VMware vSphere with Operations Management combines the most trusted server virtualization platform with the capabilities for intelligent management. With this tool you can confront virtualization’s challenges, including:

  • VM sprawl. With virtual machines easier to create, they are more difficult to manage.
  • Over provisioning. Underutilization of VMs is common.
  • Poor visibility and monitoring. With early virtualization technology, data center monitoring is reactive.
  • Complex troubleshooting. Most performance problems are slow to resolve.

Simplified management is essential to keeping pace with business expectations. vSphere with Operations Management provides an intuitive dashboard to help you assess the health of your virtualized environment, monitor risks to IT performance, and identify opportunities for greater efficiency. You’ll possess the power to address performance resolution, capacity management, and future planning for your data center, and you’ll have the solution for the “expectations gap.”

 

 

To learn more about the difference that operations management can make in your virtualized environment, read our new white paper Take Virtualization to the Next Level with vSphere with Operations Management.

 

 

 

 

 

 

Follow VMware SMB on FacebookTwitterSpiceworks and Google+ for more blog posts, conversation with your peers, and additional insights on IT issues facing small to midmarket businesses.

Four Ways a BC/DR Plan Can Help Your SMB – Part 3: Software-Based Replication

By: vExpert Gregg Robertson                        

A Business Continuity and Disaster Recovery (BC/DR) iplan s something every business, no matter how big or small, should be thinking about and implementing. Whilst preparing for my VCAP-DCD and even for my VCDX attempt, BC/DR was a very important topic, as two of the infrastructure qualities of AMPRS (Availability, Manageability, Performance, Recoverability and Security)  are availability and recoverability.

In my daily role as a consultant, BC/DR is a core component for every virtualization design, no matter if it is data center virtualization, end-user computing or hybrid cloud. In this four-part blog series, I am going to cover four ways BC/DR can help your small/midsized business (SMB) through the usage of solutions available to you. In this third blog, I will cover the benefits of automated software-based replication built in as a feature in VMware vSphere.

Automated Software-Based Replication

With the release of VMware vSphere 5.1, came the availability of vSphere Replication (VR), which was previously only available in VMware Site Recovery Manager 5.0. VR is a software-based replication engine that works at the host level rather than the array level. Identical hardware is not required between sites, and in fact, customers can run their VMs on any type of storage they choose at their site – even local storage on the vSphere hosts, and VR will still work. It provides simple and cost-efficient replication of applications to a failover site. VR is a component delivered with vSphere Essentials Plus and above editions, and also comes bundled with vCenter Site Recovery Manager. This offers protection and simple recoverability to the vast majority of VMware customers, without additional cost.

vSphere Replication allows single site replication and protection. This is perfect for SMB organizations that may have a local campus, with a single cluster spanning two floors of a building where recoverability is within a proximal datacenter. If a floor loses power and the primary hosts and disks are unreachable, the administrator could simply point to the replica VMDK within VR and choose to recover it. The administrator deploys a single VR Appliance to act as both the replication manager and also the recipient and distributor of changed blocks. Then the admin configures a VM and one or more of its VMDK files to be replicated, giving the local VR Appliance as the target, and selecting a different datastore for the replica of the VM. The vSphere Replication Agent on the appropriate vSphere 5.x host that holds the running VM then starts tracking changes to disk as they are being written, and in accordance with the configured RPO sends the changed blocks to the VR Appliance.  The VR Appliance passes the changed block bundle via NFC to a host to write the blocks to the replica VMDK.

VR is also a perfect fit for IT managers looking to protect virtual machines in ROBO scenarios.

In this model, hosts at remote sites are not managed by distributed vCenter Server instances, but from a central ‘head office’ datacenter. A single vCenter Server instance manages both local vSphere instances and remote clusters or hosts.

VMs from multiple remote sites need to be replicated to the central office in this scenario.  At the remote sites, as long as the hosts are vSphere 5.x, there is no change necessary to be implemented. They will have the necessary vSphere Replication built in to the kernel.

At the head office datacenter, at least one vSphere Replication Appliance must be deployed to manage the replication of all the VMs (both remote and local targets). This single appliance will usually be sufficient to handle the incoming replications, but sometimes customers will want to isolate replication traffic by source, or will need to scale up the number of recipient servers to handle more incoming replications.

In that case, administrators can deploy more VR Servers (Not the full VR Appliance – there is only one per vCenter) to handle isolating the incoming replication traffic or to adjust for scale.

Each VR Server can be used as a dedicated target for one or more remote sites.

Within the main datacenter, the VR Servers will pass the incoming replication data to the recovery cluster via Network File Copy for committing to local replica copies of the remote VMs.

Continue reading

Four Ways BC/DR Can Help Your SMB – Part 2: Automated High Availability

By: Gregg Robertson ,vExpert

Business Continuity and Disaster Recovery (BC/DR) is something every business, no matter how big or small, should be thinking about and planning for. Whilst preparing for my VCAP-DCD and even for my VCDX attempt, BC/DR was a very important topic, as two of the infrastructure qualities of AMPRS (Availability, Manageability, Performance, Recoverability and Security) designs should show impact on availability and recoverability.

In my daily role as a consultant, BC/DR is a core component for every virtualization design no matter if it is data center virtualization, end-user computing or hybrid cloud. In this four-part blog series, I am going to cover four different ways BC/DR can help you with your small/midsized business (SMB) IT infrastructure.  In this second blog, we will cover the benefits of automated high availability built in as a feature in VMware vSphere.

Automated High Availability For SMB’s

BC/DR is met and ensured with features that have been part of vSphere for years, like VMware High Availability (HA), which, since vSphere 5.0, has been rebuilt from the ground up to use the Fault Domain Manager (FDM) agent instead of the legacy AAM agent (Legato Automated Availability Management). This rebuilding of a new agent has introduced higher resiliency and less complexity and means that HA can be enabled with as little as five clicks and be installed onto ESXi hosts in seconds rather than the minutes that it took previously. HA allows you to protect the virtual machines running on your hosts from isolation and/or recover from host failure by restarting the virtual machines on the affected host to the remaining working hosts, thereby bringing your applications and solutions back online as soon as possible. With the new FDM agent, this also allows partitioned hosts to elect a master node within the partitioned section and maintain the uptime of the virtual machines on the affected hosts. HA also has a number of features that provide additional checks to ensure that hosts are indeed non-responsive before rebooting the virtual machines through the usage of Datastore Heartbeating and the setting of additional isolation addresses.

HA can also restart virtual machines if the application in a virtual machine fails through the usage of application monitoring. By utilizing the appropriate SDK or an application that supports VMware application monitoring, HA can setup customized heartbeats for your applications.

vSphere HA has several advantages over traditional failover solutions, including:

Minimal setup – After a vSphere HA cluster is set up, all virtual machines in the cluster get failover support without additional configuration.

Reduced hardware cost and setupThe virtual machine acts as a portable container for the applications and it can be moved among hosts. Administrators avoid duplicate configurations on multiple machines. When you use vSphere HA, you must have sufficient resources to fail over the number of hosts you want to protect with vSphere HA. However, the vCenter Server system automatically manages resources and configures clusters.

Increased application availability – Any application running inside a virtual machine has access to increased availability. Because the virtual machine can recover from hardware failure, all applications that start at boot have increased availability without increased computing needs, even if the application is not itself a clustered application. By monitoring and responding to VMware Tools heartbeats and restarting nonresponsive virtual machines, it protects against guest operating system crashes.

Distributed Resource Scheduler (DRS) and vMotion integration – If a host fails and virtual machines are restarted on other hosts, DRS can provide migration recommendations or migrate virtual machines for balanced resource allocation. If one or both of the source and destination hosts of a migration fail, vSphere HA can help recover from that failure.

High Availability Overview

Fault Domain Manager Agent

HA’s architecture is fairly simple with the FDM agent being installed on each ESXi host within a vSphere cluster that has HA enabled. As of vSphere 5.0, there is now only a single master node and all the remaining hosts within the cluster are slaves which report their health to the master node as well as the vCenter server. This is unlike HA in versions previous to vSphere 5.0, where there were Primary and Secondary nodes, which constrained you to a limit of 5 primary nodes and the need to have at least 1 primary node available. The below diagram shows a simplistic view of the FDM agent on each host and the allocation of the master and slave roles to the hosts.

Heartbeating

As of vSphere 5.0, there are now two different heartbeat mechanisms that HA uses to ensure the health of the ESXi hosts within the HA enabled cluster. The first of these is datastore heartbeating, a new feature as of vSphere 5.0. Datastore heartbeating adds an additional check where HA utilizes the existing VMFS file system locking mechanism of creating a heartbeat region. The heartbeat region is where at least one file per host is kept open per selected heartbeat datastore (default is two datastores). HA does a check whether the heartbeat region has been updated and if it has, then the host still has storage connectivity and therefore the virtual machines on the host don’t need to be restarted elsewhere. The below diagram shows the selection of three datastores and that currently, only two of the hosts within the cluster are attached to the two datastores. Good design practice is to allow HA to select the datastores, as HA will choose the datastores with the most connected hosts and if applicable NFS and FC/iSCSI datastores to ensure added resiliency.