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

Mar 29 2015

Nutanix Traffic Routing: Setting the story straight

There are many great benefits to hyper-converged technologies, the underside is that there can be some mis-understandings from the community  about how the product and architecture actually works.

Specifically there has been some discussion of late about the I/O path through the hypervisor and there appears to be a knowledge gap of how this actually works.

Let me take this opportunity to educate and clarify….

There was some mis-information recently posted stating that Nutanix extends the I/O path, forcing VM I/O to go through the hypervisor twice; being the first time when it leaves the guest VM and the second time when it leaves the Nutanix Controller VM.

While it is true that the VM traffic goes through a VSA, it is incorrect to say that VM traffic goes via the hypervisor to access disk devices twice. Nutanix uses VMDirectPath I/O pass-through to allow direct access to disk controllers and all disk devices, removing the I/O transposition. The hypervisor is actually oblivious of the SSD/HDD devices. This allows the native controller drivers to be used, avoiding any bugs that may be introduced by non-standard or custom written drivers for the hypervisor. The picture below demonstrates the simplicity of the Nutanix data path with VMDirectPath I/O.




The picture above also demonstrates that all the IO is served via the CVM, where most Read IOs are actually served from RAM providing microsecond read latency experience that Nutanix customers love; whilst unfortunately VSAN is not in the enviable position to provide such benefit because it relies solely on a single flash device per disk group per server. (read this test that generated half million IOPs with single block)

Again, most unfortunate are the claims against the VSA approach because when you look deeper at how VSAN is able to offer basic table-stakes enterprise data services you quickly notice that this story is flawed. To deliver simple day-to-day services like compression, de-duplication and encryption VSAN needs to rely on 3rd party external VSAs that are not maintained by VMware and therefore do not have any type of code inspection to ensure security and reliability.

Such these services also run in hypervisor user space and also require additional resources such as RAM and CPU for the applications and the multiple virtual machines. Furthermore, that also dismantle the ‘single throat to choke’ for support story.




I’m happy to be able to set the story straight with the VSA approach. I believe that the benefits of having an integrated and unified data services aid in providing a robust, secure and future-proof platform that at the end of the day benefits customers.


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

Permanent link to this article: http://myvirtualcloud.net/?p=6977

Mar 23 2015

Business Frequent Flyer Top Tips

Like many of you I business travel frequently. They can be a one-day trip, a week, or even couple weeks in-and-out of airports, hotels, restaurants and conferences. When frequent flying it is important to be prepared and adequately equipped.

I have learnt few tricks that make my life easier at airports and hotels, and I would like to share the ones I consider most important.


  1. Never check-in your luggage

Despite saving money ($50 to $100) it will also expedite your exit from airports; in some cases helping you to avoid taxi lines. The most important here is actually to ensure your luggage goes to the same destination as you are.

I have recently been forced to check-in my luggage in Milan with destination to Tallinn, Estonia. I arrived in Estonia, but my luggage got stuck in Berlin.

A good tip to avoid having to check-in luggage is to only use the self check-in stations. If not possible to use them, make sure you go to the airline counter without your carry-on luggage.


  1. Picking the right airport security line

This is more of an art than science, but there are couple things you should pay attention when choosing your line. Avoid lines with families and old people. Also avoid lines with people removing their watches and belts only at the x-ray machine. The shorter line is not always the fastest line. In US, if you are a permanent resident, make sure you apply for PRE or Global Entry, this will save you some time.


  1. Always find your gate before stopping for a bite or shopping

When you don’t know the airport ensure you always find your gate before heading for a bite or some shopping. Once, in a large airport, I stopped for a quick bite after customs, just to find out later that my gate was 15 minutes away and involved taking a train to the gate. I almost missed the flight – so I always find my gate before doing anything else.


  1. Find the right phone solution

There’s nothing worse than arrive on a country and not being able to be connected, not even to check the hotel address or reservation. Make sure you arrange voice and data access before you go. If you are in US, T-Mobile offers free 3G data access in over 64 countries. Free data is very handy when travelling abroad.


  1. Devices and gadgets

I commonly carry my phone, laptop and tablet for long trips. Keeping everything charged can be difficult, but not impossible. I carry with me a neat power adaptor I found in Spain; it has all the connectors and yet is very small. I use the adaptor to charge the laptop and use USB power chords to charge everything else. Many flights now have charging outlets and you can use them to keep your devices charged in between flights or while you use them. Don’t forget to charge everything before you travel.


  1. Check the in-flight entertainment options

Nothing worse than being stuck in an 11 hour flight without personal entertainment system. That has happened to me couple times when flying United Airlines. I learned my lesson and I always check the airplane details before the flight. If no personal entertainment system is available make sure you stop at iTunes or Google App Store for some serious movie and series downloads. Last case scenario; stop by the bookshop at the airport.


  1. Develop a solid packing strategy

I am still working on this one and it all depends on the length of the stay and the weather forecast at the destination; but I never break the rule of single carry-on luggage. I always try to fit everything I need in the carry-on, even if I am staying abroad for more than a week.

My general rule is to always have 5 days worth of business clothing that all match the same shoes and socks. I always take with me a double-sided belt and I wish there were double-sided socks too. If I am staying more than one week I will send couple things to the hotel’s laundry (be aware that some hotels will not do laundry on weekends). Pack only one color of pants and one (matching) jacket. This way you can optimize the accessories you need to take. This vastly reduces the amount of stuff you need to pack.

If you want to exercise, take some lightweight sneakers. Wear the heaviest things you are taking to minimize the amount of stuff you need to drag around with you.


  1. Jet Lag

I commonly struggle with jet lag. I tried every recommendation I could find on the internet and none of them really work well for me. I commonly have jet lag even after the 4th or 5th day when flying over 8 hours. The tips I have is to remain hydrated, try to land in the morning at the destination, and force yourself to remain awake all day; go for a city tour.

One time I decided to take a quick afternoon nap at the 6th day and I ended up sleeping for 6 hours, disrupting all the good work I had done catching up during the week. Avoid afternoon naps at all costs.


  1. Reward cards will provide you with  many benefits

Owning airline reward cards provide you with benefits, including priority boarding, priority upgrades and access to the airline lounge. Try to have at least one reward card for each major airline reward chain (StarAlliance, OneWorld); this will help you bump up your status quickly.

Another good way to bump up status and earn miles is to own an airline credit card. I currently own the United Airlines credit card that not only provides me with miles and status, but also doesn’t charge international fees when buying goods. Good money-saving!


Other important tips for the frequent flyer.
  • Get upgrades on flights by booking an economy ticket with a Y or B booking codes.
  • Ask for hotel upgrades when the front desk isn’t busy.
  • Ordering a special meal for the flight you will get fed first.
  • Stop by your company’s break room and load up on snacks before the trip.
  • Inflight attendants are not allowed to provide medication by regulation. Always carry Advil and other necessary medications.
  • Photograph you car park location so you don’t forget where it is.


If you have other important tips, please share them with me.


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

Permanent link to this article: http://myvirtualcloud.net/?p=6968

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