Archive
Simplified VDI Architecture – #Citrix, #XenDesktop
This is a great start of a blog series from Citrix!
There’s a perception that VDI is complicated. I’m far from being a rocket scientist, and I’ve managed to implement many successful VDI projects over the past ten years. I truly believe that VDI is one of those things that is only as complicated as you make it.
It’s like saying that driving is complicated. You’d have to be crazy [or very brave] to take your first lesson in Manhattan…during rush hour. That’s why your driving instructor starts you off on a quiet street. You need to know your boundaries. Being successful with VDI is the same – keep things simple to start with and slowly increase complexity at your own pace, when you’re ready for it.
This raises the question – what’s the quiet street equivalent of a beginner’s VDI architecture? It might not be the most optimized and efficient solution, but it would be quick to implement, do the job well and wouldn’t require specialist knowledge or skills. I’ve been thinking about this a lot lately, and I’d like to share my thoughts.
There’s a lot to consider, so I’m going to break this up over four different blog posts:
- Simplified VDI Architecture – Introduction & FlexCast
- Simplified VDI Architecture – Storage
- Simplified VDI Architecture – Provisioning
- Simplified VDI Architecture – Reference Architecture
Martin Zugec will be helping me out with this blog series and will be referring to his experience on actual customer projects that followed many of these recommendations.
XenDesktop or VDI in a Box?
First up, you need to make a decision on VDI in a Box or XenDesktop. VDI in a Box is easier to setup but does have some limitations. Check out Allen Furmanski’s excellent blog post for guidance on how to make this decision. I’m going to concentrate on XenDesktop for this post.
FlexCast
Although each FlexCast model has its own unique advantages, each additional model included adds complexity to the overall project. There is a great table in the Virtual Desktop Handbook (FlexCast Model Selection – Table 11) that provides guidance on the capabilities of each model. The main thing to note is that all scenarios, apart from offline, can be accommodated using the Hosted VDI model (XenDesktop), either with or without a Personal vDisk. It may not be the optimal selection in every instance, but it is almost always a viable solution.
There are a number of reasons why I think that XenDesktop is simpler than XenApp, including:
- Desktop applications are developed to run on desktop operating systems such as Windows XP or Windows 7. There aren’t many developers that test their applications on Windows Server 2003 or 2008. Therefore, you’re far less likely to run into application issues with XenDesktop than you are with XenApp. Even if your applications run okay on 2008 with XenApp, you’re probably going to have issues getting support from the application vendors.
- Hosting applications on multi-user operating systems can introduce additional application compatibility challenges. Users may share the same configuration files and registry hives, especially if the applications are not multi-user aware. This means that one user may change a setting that affects all other users of that server. There are a ton of tips and tricks to get these apps working correctly but we want to keep things simple and choosing XenDesktop helps us achieve this goal.
- As multiple users are hosted on the same operating system, it is important that XenApp desktops are locked down to prevent security breaches and misconfiguration that could impact all users sharing the environment. Typically, this results in an extremely controlled and restricted user experience, hindering user satisfaction and acceptance.
- With XenApp desktops, a single user can consume a disproportionate amount of resources, impacting the performance of other users sharing the same XenApp server. XenDesktop, on the other hand, allows vCPU and RAM assignments to be controlled on a per-user basis. For this reason, I strongly recommend that heavy users are hosted on XenDesktop rather than XenApp.
- With XenDesktop, it is possible to provide users with fully personalized desktops. This includes the ability for users to install their own applications.
- Unlike XenApp, XenDesktop supports generic USB redirection:
I’m a huge fan of Remote PC, especially when you consider just how simple it is to deploy. However, there are some things Remote PC just can’t do, including:
- You don’t have the flexibility to quickly provision or de-provision desktops based on business demands.
- Image management is more complicated than a virtual desktop because you can’t use MCS and PVS can be challenging with desktops outside of the data center
- You need to have a good connection between your XenDesktop Controllers and the physical desktops. Something not always available for WAN users.
Regardless, Remote PC is a great solution in many scenarios. Consider deploying Remote PC at the very start of your project. It allows you to realize immediate value while you’re designing and implementing your full VDI solution.
If XenDesktop is so much simpler why do so many projects still standardize on XenApp? It all comes down to cost – XenApp offers significantly higher levels of scalability than XenDesktop (some sources quote 300% more users). Let’s take a look at this in more detail.
Processor
The Virtual Desktop Handbook provides us with guidelines on processor requirements for both XenApp and XenDesktop (Processor Requirements by Workload – Table 22):
If processor is the bottleneck, we can estimate the scalability of XenApp and XenDesktop for a fairly typical server configuration (2×8 cores):
As you can see, XenApp offers between 17% (heavy user) and 28% (light user) more users than XenDesktop – but nowhere near 300%! Let’s put this into context, if you had 1,000 concurrent normal users, you would need seven physical servers for ‘XenDesktop: Windows 7’ and six physical servers for ‘XenApp: 2008 R2’. Is one additional server per ~1,000 users enough to justify the additional complexity of XenApp?
RAM
For RAM, the Virtual Desktop Handbook table (Memory Requirements by Workload – Table 23) shows us that ‘XenDesktop: Windows 7’ requires significantly…
Continue reading here!
//Richard
How to avoid the 7 pitfalls of desktop virtualization
Have a look at this!
When it comes to desktop virtualization, we’ve all messed up. Some of us more than others.
But the best among us tend to learn from our mistakes so we don’t repeat them. And the really smart ones learn from others’ mistakes so they don’t have to collect the bruises themselves.
That’s the spirit behind our latest eBook for desktop virtualization project teams:
The 7 Big, Bad Pitfalls of Desktop Virtualization Deployment:
Very avoidable ways things can go wrong (and how to avoid them)
This eBook is all about helping you succeed with your Citrix desktop virtualization deployments. It distills the expertise of our top Citrix consultants into seven of the most common mistakes that project teams make.
And each pitfall has a short list of evasive actions to take to make sure you don’t fall in. It’s a quick read and you’ll come away with some useful ways to keep your next project on track.
Go on: Download it now
BTW – The eBook is brought to you by the team behind the Citrix Project Accelerator, the all-singing, all-dancing desktop transformation project management environment. If you haven’t set up a project in it yet, you’re in for a treat.
Designing a virtual desktop environment? – #XenDesktop, #Citrix
This is a good blog post by Niraj Patel.
Questions: How do you successfully design a virtual desktop solution for 1,000 users? How about 10,000 users? What about 50,000 users? What are the questions you should be asking? Most importantly, where do you start?
Answer: Hire Citrix Consulting for your next virtual desktop project! OK, that is one right answer, but not the only way to do it. The successful way to design a virtual desktop environment is to follow a modular approach using the 5 layers defined within the Citrix Virtual Desktop Handbook. Breaking apart a virtual desktop project into different layers provides a modular approach that reduces risks and increase chances for your project’s success no matter how larger you’re planned deployment is. What are the 5 layers and some examples of the decisions are defined within them?
- User Layer: Recommended end-points and the required user functionality.
- Access Layer: How the user will connect to their desktop hosted in the desktop layer. Decisions for local vs. remote access, firewalls and SSL-VPN communications are addressed within this layer.
- Desktop Layer: The desktop layer contains the user’s virtual desktop and is subdivided into three components; image, applications, and personalization. Decisions related to FlexCast model, application requirements, policy, and profile design are addressed in this layer.
- Control Layer: Within the control layer decisions surrounding the management and maintenance of the overall solution are addressed. The control layer is comprised of access controllers, desktop controllers and infrastructure controllers. Access controllers support the access layer, desktop controllers support the desktop layer, and infrastructure controllers provide the underlying support for each component within the architecture.
- Hardware Layer: The hardware layer contains the physical devices required to support the entire solution, and includes servers, processors, memory and storage devices.
Want to know how to get started? Try the Citrix Project Accelerator. Input criteria around your business requirements, technical expertise, end user requirements, applications, etc. to get started on your architecture based on the 5 layer model.
Lastly, don’t forget to come see SYN318…
Continue reading here!
//Richard
#Citrix #NetScaler 10 on Amazon Web Services – #AWS
Yes, it’s here! 🙂
Mainstream IT is fast embracing the enterprise cloud transformation and selecting the right cloud networking technologies has thus quickly emerged to be an imperative. As mainstream IT adopts IaaS (Internet as a service) cloud services, they will require a combination of the elasticity and flexibility, expected of cloud offerings and the powerful advanced networking services used within emerging enterprise cloud datacenters.
Citrix® NetScaler® 10 delivers elasticity, simplicity and expandability of the cloud to enterprise cloud datacenters and already powers the largest and most successful public clouds in the world. With NetScaler 10, Citrix delivers a comprehensive cloud network platform that mainstream enterprises can leverage to fully embrace a cloud-first network design.
Citrix and Amazon Web Services (AWS) have come together to deliver industry-leading application delivery controller technology. NetScaler on AWS delivers the same services used to ensure the availability, scalability and security of the largest public and private clouds for AWS environments. Whether the need is to optimize, secure or control delivery of enterprise and cloud services, NetScaler for AWS can help accomplish these initiatives economically, and according to business demands.
The full suite of NetScaler capabilities such as availability, acceleration, offload and security functionality is available in AWS, enabling users to leverage tried-and-true NetScaler functionality such as rewrites and redirects, content caching, Citrix Access Gateway™ Enterprise SSL VPN, and application firewall within their AWS deployments. Additional benefits include usage of Citrix CloudBridge™ and Citrix Branch Repeater™ as a joint solution.
Citrix NetScaler transforms the cloud into an extension of the datacenter by eliminating the barriers to enterprise-class cloud deployments. Together, NetScaler and AWS delivers a broad set of capabilities for the Enterprise IT:
Hybrid Cloud Environment
Hybrid clouds that span enterprise datacenters and extend into AWS can benefit from the same cloud networking platform, significantly easing…
Continue reading here!
//Richard
Ten websites that teach coding and a bunch of other things – via @caleweissman
This is a great summary blog post with many good references to where you can start learning to code!
Seemingly every day there’s a new article or blog post imploring you to learn how to code. “Those who code have the power to transform their dreams into reality.” “Coding will help you keep [your job], or help you make a case for a raise.” “You should learn to program because it’s easy, it’s fun, it will increase your skill set, and… it will fundamentally change your perspective on the world.” What’s more, “If you want to start a technology company, you should learn to code.” New York City Mayor Michael Bloomberg’s New Year’s resolution was to learn how to code. Douglas Rushkoff, who calls coding “the new literacy of the digital age,” wrote an entire book about it. And didn’t Marc Andreessen say that “software is eating the world?” As a result, companies from Codecademy to edx and many others have popped up to meet this rising demand.
As a person who’s grown up in the digital age, I have often heard the cry, “digital literacy or die.” Conventional wisdom – at least today – is that in the way you know how to read and write English, “you need to have some understanding of the code that builds the Web… It is fundamental to the way the world is organized and the way people think about things these days.” If you buy that then you’ll want to start now.
But where should you go? I’ve been dabbling in the black arts, although I am by no means a ninja coder, and am ready to report back. The courses below offer everything from HTML to Python and beyond. HTML and CSS are good, because they’re the basic building blocks of Web design, and in my opinion, Python is useful, because it’s the most universal in many respects. Others say Java is better to learn, because its so prominent on the Web. I would rebut that you can learn Java from Python. Potayto. Potahto.
In any case, each program below emphasizes different pedagogical techniques and philosophies, and they are all mass market in the sense that anyone is welcome. No previous experience is necessary.
MIT Courseware Online
MIT has long been a pioneer of online courseware. One course is their Intro to Computer Science & Programming class, thought by many to be the best, most encompassing intro computing course offered. Taught by tenured MIT faculty, the online course is structured via taped lectures, written assignments, and self-assessment quizzes.
The course itself is quite rigorous as it was an intro course for MIT students. This isn’t a sort of online class you can do some parts and not the other. It requires a certain amount of pre-existing math knowhow to be truly successful. The course description says it only requires high school algebra as a prerequisite but I don’t buy this. I remember being pretty stumped by the second assignment, and I passed AP Calc with flying colors. This doesn’t mean the math is terribly high-level, but that it probably requires a certain amount of mathematical aptitude beyond algebra unless you want to spend the entire course scouring forums for help. As with any MIT course, there is an expectation that you not only know how to do a function, but why that function is performed and from where it stemmed. After attempting to follow this courseware for two sessions, I was officially stumped and dropped it.
edX
MIT and Harvard partnered up to create edX. It is a conglomeration of all of their available open courseware, along with a new department for the two institutions to perform research about the future of online courses and new pedagogical technologies. For MIT courseware, you can watch the lectures anytime, read the assignments, and self-assess. EdX has you follow the course in real time and complete the assignments and exams to receive a physical certificate from the program. It currently offers numerous classes in more subjects than just coding and far beyond the purview of Computers Science….
Continue reading here!
//Richard
Delivering #Citrix #XenApp on #Hyper-V with PVS and #McAfee – via @TonySanchez_CTX
Good Citrix blog post from Tony Sanchez!
Architectures—whether physical or virtual—should be flexible enough to adapt to different workloads, allowing them to support changing business needs. Although implementing a new IT architecture takes time and careful planning, the process to test and validate an architecture should be easy. In the case of a virtual desktop architecture, test engineers should be able to follow a repeatable pattern, step by step, simply changing out the workload to validate the architecture under different anticipated user densities, application workloads, and configuration assumptions. The procedure should be as easy as learning a new series of dance steps (think PSY’s Gangnam Style, the most watched dance video on YouTube). The point causes me as a test engineer to ask the question: in the case of VDI, why can’t a hypervisor simply learn a new workload just like I might learn a new sequence of dance steps?
Luckily for test engineers, Citrix FlexCast® provides the ability to learn and deliver any workload type by leveraging the power of the Citrix Provisioning Services® (PVS). Recently I worked with engineers from Citrix and Dell, collaborating to build a FlexCast reference architecture for deploying XenApp® and XenDesktop® on Hyper-V on a Dell infrastructure. Testing of this reference architecture looked at how XenApp and XenDesktop performed under various workloads, altering hypervisor configuration settings and examining the overall user experience and user densities. At the drop of dime, FlexCast and PVS enabled a simple switch of the architecture to a new workload.
Based on that reference architecture effort, we recently began a Single Server Scalability (SSS) test using the latest hardware and software releases available. This blog focuses on that effort — what I call the “XenApp dance step for FlexCast style” and how XenApp workloads perform on Hyper-V. (A follow-on blog article will focus on an alternate “dance” sequence for XenDesktop.) The focus of this blog is how the configuration of the McAfee virus scanning software can impact performance and scaling.
In previous blogs, I describe the testing process and methodology that leverages the Login VSI test harness, along with key tips for success. Since those same methods and recommendations apply here, let’s review the configurations we used for this scalability testing as well as the workloads and actual test results.
For background reading, I highly recommend that you review Frank Anderson’s post on XenApp physical versus virtual testing results with Hyper-V. Frank is my colleague and a great resource for insights about testing, including implementation tips and general best practices. In addition, the related Dell and Citrix white paper describing the FlexCast reference architecture for deploying XenApp and XenDesktop on Hyper-V is available here.
Continue reading here!
//Richard
#Citrix Virtual Desktop Handbook 5.x – #XenDesktop, #XenApp
Ok, this is a pretty good handbook I must admit. Have a look at it here!
And if you need help then of course you can always contact EnvokeIT! 😉
And here is a good blog post about this as well by Thomas Berger:
One of the foundational project management principals is that project success occurs when it is delivered on time, within budget and with a level of quality that is satisfactory to the client. Of course these three dimensions are valid for any desktop virtualization project as well.
While a lot of information about budget planning and TCO/ROI for virtual desktop / application delivery projects can be found on the internet (e.g. http://flexcast.citrix.com/analyzeandcompare.html), the amount of information about time planning and success criteria is very low.
Since this lack of publicly available information causes every customer to “reinvent the wheel” and therefore add some delays to their projects, we thought it’s time to provide some guidance around these topics.
The result of our efforts has become part of the newly released Citrix Virtual Desktop Handbook (http://support.citrix.com/article/CTX136546). Version 1 of this white paper focuses on the Assess phase that identifies the information required prior to starting the design phase and outlines the project management tasks I mentioned earlier.
But instead of just discussing the topics from a theoretical point of view, we provide detailed guidance and tools which can be used for your projects right away. For example you will get a sample project plan (Microsoft Project), which outlines and provides duration estimates for every step of a desktop virtualization project (sample below).
Furthermore the white paper discusses a general project methodology, describes how business priorities can be identified and provides detailed information about the roles required during a enterprise grade project (sample below).
This and even more can be found within the new Citrix Virtual Desktop Handbook..
//Richard
How does #Citrix #NetScaler SDX isolate its instances?
Ok, I received this question the other day and this article is really spot on! Get a cup of coffee and enjoy! 😉
And remember this: YOU CAN ONLY HAVE 7 INSTANCES/1Gbps NIC!!!! So if you intend to host more than 7 VPX’s on your SDX then ensure that you plan your network design if you use 1Gbps otherwise go for the 10Gbps ports and SPFS.
NetScaler SDX Appliance with SR-IOV and Intel-VTd
This article contains information about the Single Root I/O Virtualization (SR-IOV) and Intel Virtualization Technology for Directed I/O (Intel-VTd) technology and how NetScaler appliance uses this technology to achieve fully isolated high performance NetScaler instances.
NetScaler SDX Appliance with SR-IOV and Intel-VTd
Server Virtualization presents both a tremendous opportunity and a major challenge for Enterprise Data Centers and Cloud Computing infrastructure. Current Hypervisors already facilitate the consolidation of many servers that are not utilized efficiently to a smaller number of physical servers delivering better space utilization, lower power consumption, and reduced overhead costs.
Virtualization architectures are built on a virtualization layer called a Virtual Machine Monitor or Domain 0 that becomes the primary interface between a virtual machine and the physical hardware. Even though virtualization allows multiple virtual machines to share the same hardware, it also creates additional overhead and can lower server performance as it becomes the bottleneck between a virtual machine and input/output (I/O) hardware as the number of virtual machines increase.
The NetScaler SDX appliance breaks through these performance bottlenecks by leveraging next generation of I/O virtualization technology called SR-IOV as defined by the PCI-Special Interest Group (SIG). SR-IOV enabled Intel chips along with Intel VT-d enable the NetScaler SDX appliance to significantly reduce virtualized network processing overheads, and provide more secure and predictable mechanisms for sharing I/O device among multiple virtual machines.
Intel Implementation of Single Root I/O Virtualization
Intel has worked with the PCI-SIG to define the SR-IOV specification. As shown in the following image, SR-IOV provides dedicated I/O to virtual machines bypassing the software virtual switch in the Virtual Machine Manager (VMM) completely, and Intel Ethernet Controllers improve data isolation among virtual machines. Another feature of SR-IOV is a feature called Virtual Functions. These are Lightweight PCIe functions that allow a single physical port to look like multiple ports. Therefore, multiple virtual machines can now have direct assignment on the same port. This increases the scalability of the number of virtual machines on the machine through more efficient I/O device sharing.
Intel VT-d Technology
Intel VT-d is a hardware enhancement for I/O virtualization that is implemented as part of core logic chipset. Intel VT-d defines an architecture for DMA remapping that improves system reliability, enhances security and…
Continue reading here!
//Richard
It all ADDS up with #BYOD (Assess + Design + Deploy + Support = Success)
Below you can read about a couple of webinars coming up on Citrix’s view on how to get your BYOD strategy up and running!
Cowboy consumerization is here…and it’s here to stay. You may not want to admit it, but you already have a few “outlaws” in your organization who are using their own devices, regardless of whether you allow them to or not. In fact, you probably have entire departments accessing email, apps and data on devices and through services that are not secure. The consumerization of IT is here to stay, so you may as well embrace it.
When business information is accessed by user-owned, consumer-grade devices, the right technology foundation is essential to ensure IT control. The question is where to begin. What are the business, user and IT benefits of enabling bring-your-own device (BYOD)?
The business wants to make employees more productive yet remain compliant. Users want access to all their enterprise apps and data from their many devices and IT wants to ensure security and control in a way that’s simple to manage.
Before you begin a BYOD initiative, it’s important to understand the underlying products that will become a part of your BYOD solution and their functionality and feature sets. One size does not fit all and, even though a BYOD solution may seem complex, it’s important to realize that it all boils down to addressing four key things:
- Multiple Devices – Employees are bringing their own devices (on average 3) into the workplace – whether you like it or not.
- Lots of Apps – IT have lots of them and different types (Windows, Web, SaaS and Mobile) that everyone want access to from their device.
- Unmanaged Data – Employees are..
Continue reading here!
//Richard
Watch the #Citrix Consulting Best Practice Webcast Series
Citrix Consulting Best Practice Series
In these webinars, members of the Citrix Consulting team have taken an in-depth look at the steps to desktop virtualisation.
Beginning with the basics, looking at setting priorities, and passing on the knowledge needed to fully understand the processes, what is required for roll-out and of course the value of desktop virtualisation.
This series has been extremely popular and now, is available for you to view at your convenience.
Regardless of where you currently stand with your desktop virtualisation, feel free to look at a single phase or check out the whole series.
Content:
- Introduction: Desktop Virtualisation: Your Insight into the world of Desktop Virtualisation
- Phase 1: Establishing business priorities and mapping these to your desktop virtualisation project
- Phase 2: Analysis – understanding your existing IT infrastructure
- Phase 3: Design – key concepts and approaches for designing your desktop virtualisation solution
- Phase 4: Build/Test – validating your design and making improvements
- Phase 5: Rollout – Going Live and operational with your virtual desktops
Continue reading and watch the webcasts here!
//Richard
The IT Melting Pot! 