Apr 08 2015

Are PoC and Pilot no longer required for VDI deployments?

Back in 2011, in the world of SAN, I wrote an article called “VDI USER EXPERIENCE and USER ACCEPTANCE”. The article iterated through my experiences reviving failed VDI deployments due to poor technical design; mostly driven by storage performance complications.

In my article I explain that the User Experience is the interaction between users and the desktop interface, in this case Windows and the applications. User Experience can only be measured by the user perception in contrast to a known baseline. User Experience is not a metric that can be collected and analyzed.

Metrics such as CPU utilization, storage latency and network contention do not provide a user experience index. As an example, network bandwidth utilization could be low but display performance is sub-optimal due to a mis-configured display protocol. There are tools that provide in-guest analytics, but offer limited view to the wider user environment spectrum – but I still say it’s good to have them.

I then explain User Acceptance, being a consequence of a good User Experience. If the User Experience isn’t great there will be no User Acceptance, and here I find the most dramatic consequences of a not well-designed solution. If users, in their very first interaction with the new VDI environment are somewhat disappointed, it will cost time, effort and sometimes money to re-convert them; and just like in any market, if users are happy they spread the word, and if they are unhappy they will also spread the word.

yada, yada, yada… then I talk about the importance of never overlooking the VDI pilot and Proof of Concept (POC) phases. All good so far, and we all agree that POC and Pilot are essential for successful VDI rollouts.



What has changed?

Since 2011 hyper-convergence has emerged and matured, removing many of the complex aspects required to rollout successful VDI solutions.

The inexistence of dual-controllers like in centralized storage (SAN) completely removed the need to validate storage architectures under full load. The distributed nature of hyper-converged solutions warrants testing a single server under load to be enough to characterize an entire VDI deployment, independent if 100 or 100K users. You will know that for a given user profile you are able to have n users per server.

That also means that there aren’t calculations required for the number and types of disks, RAID groups, LUNS or controller overload in case of failures. Hyper-convergence implements an independent virtual controller per server; and in case of a server component failure only the desktops in that server are affected, not the entire fleet.

Finally, hyper-convergence excels when VDI deployments need to grow, not requiring complex math exercises to calculate storage performance and capacity expansions. Remember, you already know how many users of a given profile the server will support; simply add servers to the existing cluster.

Back to the POC and Pilot phases, they are still essential and you should never skip them. However, they are now much easier to be attained with a little help of hyper-convergence.


Last but not least. Make sure you select the VDI solution and supporting technologies that cater for your users need; make sure products will have longevity and have right fit for your organization. VDI can be very complex and hyper-convergence make it simpler, but look for vendors that are willing to help you with the process to augment your chances of being successful.


This article was first published by Andre Leibovici (@andreleibovici) at myvirtualcloud.net


Permanent link to this article: http://myvirtualcloud.net/?p=7016

Apr 05 2015

VDI Calculator v6.2 is Now Available w/ Haswell support

Today I am announcing the general availability of the new VDI Calculator v6.2. This version introduces support for the Xeon E5-2600 V3 family of processors, based on Haswell microarchitecture, and Configure To Order (CTO) configurations for the Nutanix NX and Dell XC series.


  • Haswell E5-16xx/26xx v3 processors – Haswell is the successor to the Ivy Bridge microarchitecture, which is the de facto processor in all Nutanix hardware platforms today. The VDI calculator now accepts Haswell E5-16xx/26xx v3 processors up to 18 cores. Please note that Haswell configurations can also be used for traditional SAN (3-tier) deployments. According to Intel, “From a performance perspective we are delivering worldwide performance levels, tripling performance [thanks to] the Xeon V3’s 18 cores [that] offer a 50 percent increase over the prior generation”. On Nutanix NX and Dell XC the storage performance improvements are visible as you can see in the graph below.




During tests with LoginVSI Knowledge worker profile we are seeing a 15 to 25% performance improvement coming from the Haswell processor, but also from the improved memory speed. On a Nutanix NX 3460 (2x10c) we now see around 125 2vCPU desktops with the aforementioned LoginVSI profile. Despite tests, I would strongly recommend a proper assessment to define the resources required by your organization’s VDI deployment.


  • Configure To Order (CTO) – Both Nutanix and Dell now provide support for Configure To Order (CTO). With this, you have the ability to right size your hardware platform to exactly meet the need of your workloads by choosing the right amount of compute, memory and storage that your VDI solution need. Given that the configuration is now flexible I have removed the rigid selection for specific Nutanix and Dell models, opening up for choice. Please make sure you verify the available models with Nutanix or Dell before setting a specific ‘Socket per Host’ and ‘Cores per Socket’ configuration.



To access the new VDI calculator click here.


This article was first published by Andre Leibovici (@andreleibovici) at myvirtualcloud.net.




Permanent link to this article: http://myvirtualcloud.net/?p=7010

Apr 04 2015

Three Free VDI options for KVM hypervisor

Most customers with VDI deployments are running Horizon View, Citrix XenDesktop and XenApp; or other smaller market players such as Dell vWorkspace and Ericom. Few early adopters are also exploring Microsoft VDI with Hyper-V and SCVMM; which has proven to be a stable platform scaling to approximately 1500 virtual desktops.

However, I see an increasing request for a Nutanix KVM supported VDI solution. Customers want to run VDI on Nutanix KVM, eliminating hypervisor license costs, therefore reducing the total cost per desktop. Furthermore it’s also possible to remove Microsoft licenses if Linux is used. Cost per desktop has been one of the big factors in VDI adoption leading to many ROI discussions.

I started looking at VDI alternatives for the KVM world and was able to find solutions that could fit the bill for some organizations. Most commercial VDI solutions that are able to broker connections to standalone machines, virtual or physical, are also capable to work with desktops hosted on KVM hypervisor. However, for the purpose of this article I am focusing on solutions that will provide zero dollar cost (except for Microsoft Windows OS).


  • Stand-Alone Windows VMs

Virtual desktops are nothing more than virtual machines running Windows or Linux operating systems. Virtual machines with remote display protocols enabled can be treated and accessed as virtual desktops.

Some Nutanix customers decided to use KVM to host stand-alone virtual machines manually provisioned. They hey use NETBIOS and DNS resolution to allow users to access their desktops, therefore each user must know or be pre-configured with the virtual desktop FQDN. For this end they are using a common naming classification for desktop naming that uses the employee’s ID.

Since they use only Windows 7 desktops they are using RDP; but Linux desktops could also be used with xRDP as an example.


Pros: Zero brokering and hypervisor cost with a simple approach. Windows Remote FX is now a good enough protocol for the large majority of use cases.

Cons: The solution requires individual desktop and DNS management, therefore easy to scale management. There’s no ability to use advanced remote protocol or VDI capabilities; such as auto refresh and recompose.


  • Ulteo

Ulteo Open Virtual Desktop (OVD) is a free application delivery platform that uses Windows Remote Desktop Services to publish desktops and applications. Ulteo offers access to Linux hosted desktop and application sessions. Ulteo integrate and seamlessly deliver sessions as a secure service to clients based on Windows, Linux, MacOS, Android and IOS. After some fiddling with the installation I was able to successfully publish Linux applications and Windows applications and desktop.




Pros: Free solution to deliver session based application in Windows or Linux. The solution works decently on a local LAN, but not recommended for remote use cases.

Cons: VDI using individual virtual desktops is not supported. Looks like Ulteo has been recently acquired and support may be available soon.


  • Crossroads

Crossroads is an open source load balance and fail over utility for TCP based services. It is a daemon running in user space, and features extensive configurability, polling of back ends using ‘wakeup calls’, detailed status reporting, ‘hooks’ for special actions when backend calls fail, and much more. Crossroads is service-independent: it is usable for HTTP(S), SSH, SMTP, DNS, or RDP connections. More info: http://geekcubo.com/2011/09/connection-broker-cross-roads-load-balancer/. This approach will allow for persistent and non-persistent desktop access, but the VM management, if needed, must be done manually.

Theoretically most load balancers nowadays have this capability, but according to the article linked above the author introduced some special support to use the load balancer as a desktop broker. I will soon test the solution and write another article with my review.



Pros: Zero brokering and hypervisor cost with simplistic approach. Offers connection load balance for non-persistent desktops. Windows Remote FX is now a good enough protocol for the large majority of use cases. The solution does not require manual DNS management.

Cons: If desktop management such as recompose and refresh is important for you may want to use a commercial solution, but it’s also possible to automate a desktop refresh every night using SYSPREP, snapshots and scripts.


In the three examples above when Windows is used as operating system it is possible to have Active Directory integration and authentication, printing (albeit not universal), USB sharing and a good enough remote experience. Microsoft has made its remote desktop client available for many platforms, including iOS, Mac and Android.

Commercial products offer many additional advantages, but for companies looking for a cost-effective alternative running on Nutanix KVM hypervisor you should look at one of these options. Also, please note that other solutions such as Leostream will support KVM using Red Hat Enterprise Virtualization (RHEV). In saying that, Nutanix is actively working with partners to make advanced VDI management on Nutanix KVM a reality and you should hear more on this soon.


If you using another method to deliver VDI that I have not shared here, please let me know.


This article was first published by Andre Leibovici (@andreleibovici) at myvirtualcloud.net.

Permanent link to this article: http://myvirtualcloud.net/?p=6996

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