A new version of the white theme for web interface has been published.
the article ID is ctx119509.
While I was updating this article I found a few things I thought I would share.
Someone in a different forum was trying to find the style sheet by searching for *.css. This sounds reasonable, in fact I did the same thing. The style sheets are aggregated together by an aspx page named styles.aspx.
The files themselves are actually includes and have the extension inc.
The best way to find them is to search for the word style.
There is a navStyle, fullStyle, etc.

Remember each of these style sheets is aggregated together. The Style closest to the element in question will supersede any previously specified styles.
I hope this info helps you customize web interface to look the way you want.

I joined Citrix in 2002 as a developer when we were still a single product company (MetaFrame) of about 1,800 employees and revenues of appx $500m. Since then, we've had magnificient growth in nearly every possible metric - revenues, employees, customers, market share and strategic importance to IT. Working behind the scenes to make it all happen are XenApp's 18 different Technology Component teams working around the clock in 5 different countries to develop 450 product binaries and rigorously test 320 build layouts throughout the project cycle. With this enormity and explosive growth, the question of "How do we deliver products that bring the most value to IT at the lowest cost in the shortest time?" is one that our engineering teams deal with in every product release cycle.

In the last 10 months, being on the Release Team for XenApp, I learned 10 valuable lessons in software engineering management (in addition to losing weight, sleep and some hair ). Although these observations may be based on Citrix-specific examples, I believe that in here are universal truths that apply not just to software development at Citrix but any large IT or software project. Secondly, I want you to get an insight into what some of our engineering processes are like.

Lesson 1: Tackle cross-team dependencies first

XenApp Platinum Edition has many components with numerous cross-team dependencies. If you are a team that owns an SDK (even a couple of APIs or modules for another team to consume), focus on those first before worrying about your internal milestones. You ask why? There are two reasons. First, the team that consumes your interfaces might in turn have other important milestones that depend on this SDK being delivered on time. You can't starve them. Second, most problems arise from these touch points. Eg: RPC calls, 32-bit consumers vs 64-bit SDK, logistics of releasing an SDK are not trivial - build, install issues are often unaccounted for and/or overlooked. That is why it is important to at least provide a skeletal interface (that returns dummy data) and fill in the meat later. Remember - it is better to be somewhat correct than precisely wrong.

Lesson 2: Refactor gradually, not all at once
Our natural tendency as engineers is to try and build the best performing, ideally architected, and most logically modular components. Realistically, it is impossible to score on all these fronts unless you have infinite time. Software engineers are builders and architects. They are extremely passionate about their buildings (code). We often come up with grandiose ideas of re-writing entire components with the latest available technology to try and make it all better and new, this time. But it just doesn't work like that. Here are the pitfalls in "grand" refactoring -

•Grand refactoring comes at a huge upfront cost that we tend to ignore (most of this is in reverse-engineering legacy code). These costs are hard to justify to managers in a tough economy like this, especially when everything is working as is.

• There is no guarantee that refactored code will perform better. The original engineer who wrote that code made certain design decisions consciously (might have been subtle compromises). Statistically speaking, the new engineers who are doing the refactoring are no smarter than the original authors of the code. So don't touch something if it is not completely broken.

• By the time you are half-way into refactoring, it is quite likely that a new set of requirements may come in that contradict your refactoring plan.

I am not against refactoring. Here's what I think is the best approach to refactoring:
• Identify the top problematic areas (in key measures such as maintainability, performance and security) and start by going after those first.

• Learn from smaller refactoring undertakings before you take a big step (think big but start small).

• Advertise refactoring improvements. If a modest investment got you a big gain, blog about it, share your experiences so others can learn from it.

• Refactoring must be continuous (in my opinion, every release should layout 5-7% of $$$ for refactoring improvements) but don't overdo it.

Lesson 3: Don't overestimate demos
Demos are a great way to reveal earned value. It helps to showcase engineering innovation, secure (or maintain) funding and most importantly give confidence in your design. But demo's that show PoC's (proof of concepts) should not be mistaken for end-products. We take several short-cuts when doing demos. There is a long way between demo/prototype quality and release quality that you need to account for in your project plan.

Lesson 4: Don't underestimate integrations
When an novice engineer says "Oh its easy, will take 10 minutes to do", they are almost always wrong. This is especially true of system integration. The convenience of having a VBL (Virtual Build Lab, a sort of private tree for building code) for isolated and disruptive development does not come for free (unless you are isolated by binary based releases, even there you may have a cost arising from dependency alignment). Integrations don't end when your code compiles. It all needs to work (in Citrix, we use a product-wide test automation framework that runs on every build to ascertain quality metrics on a continuous basis). Assign a generous amount of time to do integrations.

Lesson 5: Automation is not a silver bullet
There is a sign in the first floor's break room in our main XenApp engineering building here in Ft. Lauderdale that says "Automation is not a silver bullet". Keep a copy of it in your office. Certain code lends itself well to automation and certain classes of code do not. Like refactoring, here are some thoughts I have on automation:

• Full-fledged automation comes at a huge fixed cost. If your payback period is more than 3 years, re-think. We are in a fast-paced industry. The scenario or code that you automate now, may be far less important (or not even applicable) 2-3 years from now.

• There is code that can be tested very effectively using automation (eg: session management, capacity and load management), and some that just can't be (multimedia). 100% automation is impractical (trying to achieve 100% of anything is somewhat impractical for that matter).

• Automation also needs continuous maintenance. For example, if you author automated unit tests, you need to make sure a. they keep running release after release and b. they keep passing release after release. As code changes, the way it is tested may also need to change. So while calculating payback, be sure to attach a maintenance cost for every test you author.

• Like refactoring, I believe automation effort is one of those things that you have to include for each release, but not overdo it. Start with automating the biggest bang for the buck.

Lesson 6: Keep processes lightweight, yet efficient
As part of the Release Team, I have an obligation to make sure that release processes facilitate and not burden Technology Component (TC) teams. Citrix's processes have evolved greatly since we started. When Citrix had less than 10 engineers in the late 80s, they used to keep track of bugs on a single common whiteboard! Simple yet effective. 20 years later, we have sophisticated bug tracking and requirements management systems. But yet we still strive for the same simplicity and effectiveness that we had 20 years ago. To that effect, we introduced a number of process improvements:

• Formal requirements authoring processes take backstage, instead lightweight feature specs with visuals, screenshots and video demos take center-stage. We need to document things that need to be communicated, not every possible thing one can ask.

• Formalized Graphical Test Plans only where it makes sense (for complete end-end features, not for individual components or modules).

• For features submissions that are surgical changes, you don't need to produce a full code coverage report (cost doesn't always justify the benefit). But make sure you methodically and carefully step-through code changes with various inputs.

• Test automation only where ROI can be justified.

• No more separate low level and high level design documents. They can be combined into one that is readable by both technical and non-technical audiences.　

Lesson 7: Cross-team hand-off is more than just being code-complete
With a process methodology that is component-centric, we "deliver" frameworks, "release" SDKs or "hand-off" API sets. I get really upset when a team makes tall claims to have done one of these things without having a single consumer try it out first. How do you know that your hand-off meets the requirements of the SDK consumer? Does it even work? Did you factor in the time that it takes to write an installer and release a build, tasks that go hand-in-hand with releasing something? I really think Hand-offs must be signed not by the team that releases it, but by the team that actually consumes it.

Lesson 8: Component complexity is multiplicative, not additive
The amount of cross-team dependencies that we have in our product is amazing. This is no different from any other mature product of our size. Don't underestimate this when taking on a new project. If 20 TC teams each take on a project with a complexity of n, the overall complexity of the release becomes n^20, not 20n. This is due to the high cost of integration and integration testing. Keep this in mind before you take on a new feature. Often, less is more.

Lesson 9: What quality means...
The definition of quality has changed in the least 2 decades. The 80s and 90s were about trying to achieve high quality control. If there was no Six Sigma or SEI certification, you were considered an outcast. Things have changed since then. In the age of well-designed products like the iPhone, Windows 7, Google maps, Amazon and Salesforce, strong visual appeal, good design and usability are now taking center-stage. This has been true for Citrix as well. In the last few years, our focus has been shifting from a blind, knee-jerk, single-dimension view on "bug counts" to taking a more practical approach of solving real customer pain-points (for example: XA5 for Win2003 IMA resiliency, VM Hosted Apps, etc) and making some smart investments in design and intuitive visual appeal (Dazzle, Receiver, etc). Also, we've been constantly keeping maintenance costs low and passing on the cost benefits to our customers, by shedding expensive baggage (high cost, niche legacy feature deprecation and removal of code that is no longer executed). Keep looking for these opportunities at the code level.

Lesson 10: Balance Idealism and practicality
This is really the biggest lesson that I've learned. You can't achieve your ideal vision in one release. Be practical and be patient. Go after hard and known technical problems one at a time. Build on small successes to springboard you to the next level. Enterprise products and quality are built like concentric circles, inside - out. Create and follow a roadmap to your ultimate vision.

XenApp Expert Series - Informational, News, Interviews (2009) The show where we interview the experts to get you the latest research and technology news on XenApp application virtualization. Host Vinny Sosa (@vinnysosa) interviews Citrix Architect Joe Nord on application streaming and enhancements coming in XenApp 5 Feature Pack 2. Episode 7, Season 1.

View this Episode Subscribe to the series

Listen to this episode Listen to archived episodes: Episode 6: VMHosted Apps with Modesto Tabares Episode 5: Power and Capacity Management with Juliano Maldaner Episode 4: HDX MediaStream for Flash with Juan Rivera Episode 3: An Overview of HDX with Derek Thorslund Episode 2: Profile Management with David Wagner Episode 1: Power Management with Sridhar Mullapudi

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Sounds pretty complicated doesn't it.  Well in fact it can be.  When I was marketing data plans at Cingular Wireless we employed a firm who did nothing but sort through and analyze reams of data from our customer base (54 million subscribers) and find the sweet spot for maximizing our advertising, sales programs and promotions. But what if you are an emerging business not quite at the Fortune 100 level yet?  Can you still take advantage of these techniques and use them to grow your business.  ABSOLUTELY!  In this electronic, e-Marketing, Web based business world, you'd be foolish not to.

But where do you start?  Do you have to employ an Analytics firm with a gaggle of Mathematics PhD's?  Not quite.  There is some very good information (publically) available about how to get the most out of your efforts to market in the new millennium economy.  Business Week recently ran an article entitled "The Web Knows What You Want" (July 27, 2009 edition).  They also have a fantastic resource online... Predictive Analytics Delivers Value Across Business Applications.  There you will find methods on subjects such as Direct Marketing - Customer Responses, Behavior Based Advertising - Which ad customers will click on and Email Targeting - Which message customers will respond to.

As an example of these techniques I'd like to share with you some methods and analytics from this blog series.  First and foremost it is important to pick a subject matter that fits your business model and the audience you are trying to reach.  Note that every article published in this series is directed at people who are interested in CITRIX, SaaS, CLOUD, SERVICE PROVIDER and VIRTUALIZATION.  Each title and subsequent verbiage in the series uses these specific key words so that search engine optimization (SEO) is invoked.  Also, care is taken to insure relevant information is available (published online) whenever a major corporate event is taking place.  People have a higher level of interest in specific topics (and in your company) when they are going to spend money to get to a venue.  In the trend chart below, note the increase in viewer traffic before and during our Synergy and iForum (Europe) events (May-June).

One of the keys to engage people in e-Marketing through social media is writing about topics that are both newsworthy and have some kind of personal impact.   Once you gain an interest level or following, your potential to introduce product/service relevancy is greatly enhanced.  Why?  Because you're not just throwing marketing jargon around and there is a specific value to the writing that pertains to the need of the reader.  Social Media Marketing is also effective because you have the opportunity to grow the base of readers over time.  Note the graph below that depicts the aggregate views of all blogs in this series.  As people resonate with one topic, they are more likely to read more from the same author.

Most importantly, you should keep your messages short and concise... Doh!  I just violated that point with a two page blog!  Sooooo, in closing create your e-marketing programs with relevancy for the reader, venue awareness and personal impact in mind.  Save the flash and hoopla for major events and try to be CONCISE. 
 

As we now have the desktp virtualization design discussion going, I want to look at the next big question... Should I do XenApp or XenDesktop? Can I get by with Terminal Services or do I need VDI? Spend just a little time going through tweets, blogs and articles related to desktop virtualization and you will be left in the same place you started, asking the simple question "Should I do this or am I crazy?"  When I think about the desktop (I really need to have a better imagination) it isn't focused on what solution to pick, or which vendor to pick... It is focused on one simple concept:

Delivering the Correct Application to the Correct User in the Best Manner Possible

• What is the correct application? The one the user wants
• Who is the correct user? The one making the request
• How should it be delivered?  That is the tricky question isn't it.  This is where we all struggle to make headway, we keep stalling because we just aren't sure.  Why is the decision so difficult? Because users are very demanding. User keep the organization functioning.  If you hurt the user, you hurt the organization, which means you will hurt yourself (bye bye promotion, raise, or job).  
  

So how do you make the right decision? By realizing three simple truths:

1. One size does NOT fit all
2. Applications are unique
3. User's requirements change
   

Trying to align the users, applications and devices into a single, coherent desktop virtualization solution seems like a daunting task, but if you follow a few guidelines the process is doable.  For example, if a user comes to work with their own personal laptop, can I simply deliver them a hosted virtual desktop or will they need a local virtual desktop? What about users with a 3-4 year old PC?  What can I do with that setup? 

This is why I suggest you take a look at the following, recently published, white paper focusing on the deciding factors between VDI and Terminal Services-based solution. If you want a highlight of the article, it is that the whole debate is not even a debate at all. 

What do you think? 

Daniel - Lead Architect - Worldwide Consulting Solutions

Follow me on Twitter: http://www.twitter.com/djfeller

Follow me in the Blogs: http://community.citrix.com/blogs/citrite/danielf
  

Motivation
ICA winstation driver(wdica!KeyboardScanCodes()) always passes the following keyboard input data structure down to termdd!IcaChannelInput() in Shadow_Stack a.k.a passthru stack when user finished Shadow by entering Hotkey "Ctrl + " and remained that key in the previous shadower session. This means to cause SAS dialog by only "Alt" key down.

Debugging and some comments

PROCESS 820d5bc8 SessionId: 0 Cid: 09cc Peb: 7ffdf000 ParentCid: 01f4
DirBase: 0fdee3e0 ObjectTable: e1487130 HandleCount: 413.
Image: svchost.exe

scancode member for keyboard make in KeyboardInputData structure
~ snips ~
MakeCode : 0x1d
Flags : 0
~ snips

This scancode deliver causes to remain win32k!gfsSASModifieresDown(2) in previous shadower session.This is perfomed at win32k!xxxKeyEvent() to remains Ctrl / Shift / Alt key are really phisically down. At this moment, win32k!gfsSASModifieresDown(2) and win32k!gfsSASModifiers(3) by default.

In a mean time, user enteted "Alt" key in previous shadower session then add modifier ALT(1) to win32k!gfsSASModifieresDown(2) win32k!gfsSASModifieresDown became 3 which is SAS modifier Hotkey. then SAS dialog popped up in the previous shadower session as a result of entering "Del" key in win32k!IsSAS().

On the other hand, RDP winstation driver passes keyboard input data structure down to termdd!IcaChannelInput() in Shadow Stack as the same as ICA passthru stack. However, modify Flags member in keyboard data structure to 0x10. This implementation prevented from the same issue so that remains win32k!gfsSASModifieresDown(2) in previous shadower session.

useful conditional break point
The following conditional break patching was effective in this ica shadowing scenario.
0 e f768a096 0001 (0001) termdd!IcaChannelInput "j poi(@esp+8) = 0 & poi(poi(esp+14)+2) = 0x1d'!process -1 0;kv;ew poi(esp+14)+4 0x10;gc';'gc'"

Global Escalation Manager Tokyo
-fb

 Device Mapper Multipath Enablement
Kit for HP StorageWorks Disk Arrays

http://bizsupport1.austin.hp.com/bc/docs/support/SupportManual/c01683837/c01683837.pdf

Before I head off for a two-week vacation, I wanted to share a NetScaler VPX how-to video on compression that I posted to Citrix TV.

This video shows how configuring a virtual NetScaler system is very similar to configuring a physical system. If this video piques your interest, then be sure to check out our CNS-200-1I Basic Administration for Citrix NetScaler 9.0 5-day instructor-led training course, which is a great way to prepare yourself to administer any NetScaler implementation. Click here for more information.

I also wanted to let everyone know that we are still on target to release the updated CNS-300-2I Advanced Administration for Citrix NetScaler 9.0 Platinum Edition five-day instructor-led training class in Q4 2009. This course is a great way for experienced NetScaler administrators who have already taken our basic NetScaler administration to enhance their knowledge and skills further. Check out my last blog for more information.

Talk to you in two weeks!

Windows Server 2003 is dominant today in Citrix XenApp environments. In fact we are currently at the peak (or nearly so) for a W2k3 installed base for Windows servers in general. As our customers look forward they will be faced with some potentially thorny issues when moving to Windows Server 2008. The main question is whether to go to the first W2k8 release (I will call it "R1" for the sake of simplicity) which includes both 32-bit and 64-bit versions or to skip R1 entirely and go with the recently released R2 which only supports 64-bit.

Based on several discussions we have had with partners and customers there seems to be a continuum of opinions. On the one extreme we hear folks saying that they will stick with 32-bit until it is ripped away from their cold, dead hands. These are among the more conservative who fear the expense and churn of having to validate all of their thousands of 32-bit applications on a 64-bit environment. They have told us they will stay on W2k3 until extended support is complete and then probably go to R1 and milk that for all it's worth to avoid the inevitable. That would mean sticking with a 32-bit OS until possibly 2018 (should we all be retired by then?) going by the Microsoft Lifecycle table for Windows Server 2008! On the other extreme are a few bleeding edge types who have decided to skip R1 and go directly to R2 and bite the 64-bit bullet at the same time as they migrate their environment from W2k3 to the newer OS. In between are those who will move cautiously if begrudgingly over time to the new OS version to avoid falling into the extended maintenance window.

One of the main concerns is, of course, that R2 is 64-bit only. While Microsoft has been stating for some time that Windows on Windows 64 (WoW64) will solve the problems associated with running 32-bit apps on x64 platforms, many customers are still worried about 32-bit apps with 16-bit installers and the ever-present 32-bit drivers. Not to mention, 16-bit apps. None of these will not work on WoW64 environments. On the other hand, don't customers have to test all their apps when transitioning from one OS platform (W2k3) to another (R1 or R2) anyway? What extra work is involved when validating apps on x64 versus just transitioning from one version of the OS to another? Of course out lives would be easier if everyone hopped to the new OS version ASAP so we did not have multiple platforms to support but the reality is quite different. We need to know what your thoughts and plans are on this one.

So this brings me to my questions for the community:

• What do you have to say as customers and partners?
• Will you stick to 32-bit as long as humanly possible?
• Do you have older apps with 16-bit installers or 16-bit apps? What is the plan there? Re-write or retire?
• What will you do about 32-bit drivers? Printer drivers? Will XenApp's Universal Print Driver solution be the answer?
• What has been the experience for those who have made the switch to 64-bit?

Give us your comments and take the poll below.

For future updates, follow me on Twitter.

If you currently hold a Citrix Certified Enterprise Administrator (CCEA) or Citrix Certified Integration Architect (CCIA) certification, did you know that update paths are available for both the upcoming CCEE (Citrix Certified Enterprise Engineer) and CCIA for Virtualization? These update paths give seasoned Citrix pros the opportunity to update their credentials without taking five or six exams. The idea behind these update paths is to test candidates on new required skills, not on skills they already possess through previous certification.

To find out more and how you can prepare, go to www.citrix.com/CCEEupdate or www.citrix.com/CCIAupdate

The recent announcement of the Terremark Cloud offering has raised significant attention especially because of the competitive pricing and EC2 like features of elastic capacity and hourly charges with no commitment. On the surface the Terremark entry price of $0.036 per hour seems very low compared to Amazon EC2 at $0.10 but it's worth picking a few examples to provide a more apples to apples comparison.

..
Not included in the comparison is the difference in storage costs which can be small or very significant depending on the circumstance. Amazon provides up to 160 GB of instance storage for a small image or 850 GB for a large included in the hourly cost. If you have only a small instance say 10GB that adds $ 2.50 to the monthly price at Terremark ( @ .25/GB ) however of you needed the 850 GB included in the Amazon Large image that would add $ 212 to the monthly Terremark costs. Also not included is bandwidth costs, however both charge the same $0.17 GB for data transfer out . ( Although Amazon charges $ 0.10/GB for data in vs Terremark $ 0.17 data in ).

Some the bigger differences will more likely depend on how the VMs are utilized. The numbers stated above assume a full month of 24x31 operation. With Amazon EC2 it's possible to save in S3 ( bundle in Amazon terms ) an instance and then shut down ( terminate ) the VM and the billing stops. With Terremark however although you can shut down the VM, the hourly charges do not stop. Only deleting the VM ends the billing, there does not appear to be an option of saving with the hourly charges turned off and allowing a new instance from the saved image to be started at a later time. This appears to be a big advantage for Amazon although I need to learn more about the Terremark offering to fully appreciate the capabilities.

Certainly economics is not the only factor in selecting a Cloud infrastructure provider. Vendor Lock-in and VM portablity often come up as concerns. Security is also a factor in regard to Cloud computing and this was a motivator for Amazons recent Virtual Private Cloud offering which provides a dedicated VPN connection from a customer premise to an isolated Cloud inside the Amazon infrastructure. I also have to admit I was impressed with a recent tour of the Terremark data center in Miami , this place was like a high tech Fort Knox when it came to security. The entire topic of Cloud security is worthy of specialized consideration not covered in this simple comparison.

Ease of use is another consideration that is worth evaluating. The Amazon Web Console is limited in function but easy to use plus includes access to many partner and community provided ( including Citrix C3 Lab ) templates that are prebuilt and ready to launch. In Amazon EC2 for example its now possible signup and launch your own XenApp server in as little a 15 minutes.

Terremark also provides a web base console that looks straight forward however I have not used it myself yet. Terramark does not provide the same portfolio of 3rd party templates however they do provide more granularity in the size of VMs and RAM plus they offer multiple versions of Windows Server.

As the options for Cloud Computing continue to expand the economic analysis of Cloud vs Premise will extend to Cloud vs Cloud, as Service Providers continue to provide dynamic cloud type offerings.

Cloud Economics 101 Part 1 - Premise vs Cloud vs Colo
Cloud Economics 101 Part 2 - Premise Plus Cloud
Cloud Economics 101 Part 3 - Amazon Reserved Pricing

http://twitter.com/chrisfleck

Get ready for another European Geek Out event at this year's CUGtech event being hosted by Citrix Users Group Norway on Oct 7 through Oct 9 at the Dr. Holms Hotel in Geilo, Norway

This will be HARDCORE technical stuff with some of the best geeks in the world!
Shawn Bass and Benny Tritsch are coming! So are Alex Yushchenko, the founder and master of PubForum! We also have our danish friend Rene Vester from DKCUG on the speakers list! From Citrix we will have speakers from Citrix Support and Citrix Consulting, and from US our dear friends Rich Crusco and Rick Dehlinger are coming.

If you don't know about Citrix Users Group Norway, climb out from under that rock you have been living under, and come and join us at one of Europe's premier independently run Citrix Users Group events.

Click below to learn more:

CUGtech Autumn 2009: http://cug.no/cugtech-autumn-2009/
Location: http://cug.no/cugtech-autumn-2009/location/
Transport: http://cug.no/cugtech-autumn-2009/transport/
Speakers: http://cug.no/cugtech-autumn-2009/speakers/
Agenda: http://cug.no/cugtech-autumn-2009/agenda/
Master Classes: http://cug.no/cugtech-autumn-2009/master-classes/
Register: http://cug.no/cugtech-autumn-2009/register/

Stay tuned for more announcements about when registration will be made avaialble

After my first blog, I received a few comments focused about user-installed applications and how there isn't much talk about them.  Faisal posted a comment that stated he was doing a pilot with XenDesktop.  Right now the biggest complaint is that users can't install their own "personal" applications  and this is one of the big questions regarding virtual desktops.  We had a few comments from others wanting to know the same thing (some really good posts). Well, here are my thoughts

With a physical desktop model, users could essentially do just about anything to their workstation.  How much of a good thing was this?  It makes the user happy, but what are the associated risks? 

1. Managing the endpoint became a nightmare. Hard to know what application conflicts will ensue with these unknown applications.
2. Introduction of viruses, malware, spyware, etc.  Many of the applications users install are freeware/shareware from untrustworthy sites.  If it is on the desktop, does it now have the freedom to inflict damage to the rest of the network?
3. Workstations became bloated and eventually slowed to a crawl resulting in IT having to completely rebuild the workstation.
   

Let's now move to the desktop virtualization model.  If we are using hosted virtual desktops, that typically means the desktop is now operating within the confines of the data center.  If you allow users to install applications onto their hosted virtual desktop, in my opinion, you might as well just open the doors to your data center and let anyone in because that is what you are doing if you let users install anything.  Doesn't that concern you?  If not, try telling this to a security person within the organization. After they recover from their stroke, they will tell you why this is not a good idea.

Now I'm not saying that we can't and shouldn't allow user-installed applications, I just want to make sure everyone understands the risks with doing such a thing.  With the 3rd party solutions that are out there (AppSense and Atlantis Computing were mentioned in the comments from a previous blog post), my question would be

1. How do we protect the data center from unknown apps.
2. How do we keep the virtual desktop optimized and supportable. I don't want manage more bloated desktops By the way, this makes a great case for a Bring Your Own Computer (BYOC or BYOPC) model.
   

I do just want to add one more point.  I've been using a hosted virtual desktop for about 2 months now with a shared disk, so any changes I make (application installs) go away after reboot.  Truthfully, I haven't had much of a problem.  I did need to download and install a few freeware tools to help me finish a project, but I only used those items for about 2 hrs.  The nice thing, in this instance, was after I rebooted, they were gone.  I don't plan on using them again. And if I do, I'll just re-install. Of course this isn't an application I need. 

So the final question is should we really allow user-installed applications to persist or should we have a process in place where IT can quickly virtualize and deliver these applications to the respective users through a standardized application delivery approach?   

Daniel - Lead Architect - Worldwide Consulting Solutions
Follow me on Twitter: http://www.twitter.com/djfeller
Follow me in the Blogs: http://community.citrix.com/blogs/citrite/danielf
  

Starting next week, Citrix will be accepting speaking proposals for our big Synergy conference, May 11-14 in San Francisco.   Synergy is focused on the growing convergence between virtualization, networking, and cloud computing.  Because interoperability and openness are central to this theme, we'd like to encourage technical experts and thought leaders around the industry to contribute proposals that focus on a wide range of real world topics, not just those that center exclusively on Citrix technologies. While we're obviously very proud of our own solutions and welcome submissions that feature Citrix, we also believe customers are best served when vendors provide open forums that deal with the real challenges and issues they face every day, especially when those issues involve getting products from multiple vendors to work well together.

With this in mind, we'd love to hear your ideas for topics you think would make great sessions at Synergy. This is your chance to share innovative ideas about how to break from the costs and complexities of the distributed computing status quo and build a SIMPLER and more cost efficient computing environment.

Synergy call for topics submissions will be judged by a selection committee that includes independent analysts, journalists and enterprise IT professionals - we will be naming names soon, and promise a few surprises!   The committees will be looking for compelling, technically rich content that details proven and innovative ways to use virtualization, networking and cloud computing concepts to create a dynamic, agile IT infrastructure.  Don't be afraid to be edgy, provocative and creative. We want sessions that tackle the real world technical and business issues customers are dealing with today, not just vendor sales pitches.

In general, we are looking for submissions that address trends, technologies, and proven solutions in the following areas:

• Desktop virtualization
• Application virtualization
• Server virtualization
• Cloud computing
• Application networking

Check out the Synergy site for more information and to submit your topic!  We're really looking forward to getting input from the larger community since there seems to be a great deal of energy for an open conference on these topics. We want to hear from you!

I don't care what anyone says, it's really not that hard to virtualize a desktop.  The hard part is delivering virtual apps and desktops to users in a way that's so fast... so smooth... so seamless, they don't even realize it's not running locally. Believe me, THAT is no easy task. Introduce a slight mouse delay or drop a few frames, and users go nuts.

Citrix has spent more than 20 years refining and improving user experience for virtual desktops and apps. During that time, we've faced every imaginable combination of users, devices, networks, drivers, peripherals and applications. And for each new challenge, we've gone back to the drawing board to develop, optimize and refine technology from the datacenter to the device to ensure a "high-definition experience," using the least bandwidth possible. When you do something for more than 20 years, you tend to become fanatically focused on the details. You also tend to get really good at it. That's exactly what the HDX Technology in our Citrix XenDesktop and XenApp product lines is all about.

But while I'll stand our HDX Technology up against anything in the industry, there is one class of applications that have admittedly been almost impossible to do well in a virtual desktop environment in the past. Apps with high-end 3D professional graphics such as Dassault Catia, Autodesk Inventor, ESRI ArcGIS or Siemens NX are so demanding, they have simply been impractical to do in most cases without running the app and all its data on a local PC or workstation. 

This is unfortunate since the manufacturing companies who are the heaviest users of these apps are often those who have the most to gain from the flexibility, security and cost saving benefits of virtualizing these apps and running them centrally.  Because many of their users are in offshore locations, intellectual property concerns are high.  And since offshoring partners tend to be a long distance away and can only work with data that stays securely in the customer datacenter, WAN performance is absolutely critical. When it comes to engineers and designers working with complex 3D models, you simply can't afford to settle for anything less than a true high-definition experience.

Earlier this week, we officially unveiled our new HDX 3D technology, breaking through this barrier for the first time ever. Many of those familiar with Citrix, however, know that we've been working on the technology needed to deliver these high-end graphical apps (and the enormous data models they use) for a few years now.  During that time, we've had several high profile projects underway to address various aspects of this problem, including Projects Pictor, Apollo and Prism... all of which you've probably heard about in blogs, events and user conferences.  So which of these efforts lead to the final breakthrough that is now HDX 3D? Here's the inside scoop on how it played out.

From early on, there were a number of technologies on the market designed to "remote" 3D graphical apps. At the same time, it was pretty clear from the beginning that none of them worked in a true WAN environment.  While this was obvious from our own testing, it was even more apparent by the number of customers who asked us for a solution even after purchasing other 3D graphical application remoting solutions (some quite expensive, I might add).  Issues like lag, overshoot and mouse delay were driving users crazy as they constantly chased their models around the screen and waited for skittish refreshes.  As I mentioned above, it's not hard to virtualize a desktop or an application - it's just hard to make it feel like it's local. 
While figuring out how to perform seamlessly over a WAN was obviously critical, we also found out that unlimited bandwidth LAN environments could be just as much of a challenge as tightly constrained WAN scenarios.  While virtualized 3D apps tend to perform better on the LAN, customers quickly discovered that they could easily consume up to 30 to 40 Mbps of bandwidth on average. 

Clearly this too was a non-starter. In many ways it reminded me of when I bought my last car. After all the papers were signed, the salesperson walked me through all the buttons and dials, and casually slid into the conversation the fact that the car took only the most expensive grade of fuel. Not the kind of surprise you want to find out about after-the-fact.

Probably the best news of all from a customer perspective is that HDX 3D is a built-in feature of Citrix XenDesktop Advanced, Enterprise and Platinum editions at no additional charge.  It runs on a dedicated blade or server with a dedicated GPU, but is managed alongside regular XenDesktop users - providing a single infrastructure that serves everyone.  

It's pretty easy to sum it all up:  HDX 3D for does the same thing for 3D graphical applications as the rest of our HDX technologies do for regular applications.  At the end of the day, it all boils down to user experience and cost.  You can talk all day about the flexibility and security benefits of centrally managed desktops, but if users have a bad experience... or if you blow out your network costs in the process, you haven't solved the problem. Luckily with HDX you have both.  And with our new HDX 3D technology, we've finally broken this barrier for the most demanding professional graphics apps in the industry.

But now for the REAL question on the mind of all you Citrix fans who have been following us on this journey... "Which of those graphics acceleration projects we heard so much about became HDX 3D?" Was it Project Pictor? Or Project Apollo? Or maybe the more recent Project Prism?" Or were these all really just the same thing under different names to keep people guessing?

The answer is actually pretty simple. Project Pictor, our first major investment in this area, was based entirely on a XenApp architecture.  Project Apollo, a parallel effort that started a bit later, set out to accomplish the same goals on a XenDesktop based architecture.  As we worked through these two projects, it became clear that both had strengths and weaknesses.  At the end of the day, we decided to combine the strengths of both projects under a new initiative dubbed Project Prism. It is this final combined effort that will debut later this month as the new HDX 3D feature of XenDesktop. 

I have personally tested all of the other solutions in the market today and can assure you that XenDesktop with HDX 3D provides the best user experience over the WAN hands down... AND uses dramatically less bandwidth over the LAN. Getting there was no easy task, but I can promise you that taking the time to get it right was well worth the journey.

Over the past several days I have been assisting one of my colleagues with troubleshooting a Web Interface for SharePoint (WISP) 2007 "Unknown Error" issue.

The problem we initially had was that the error as stated was... Unknown!

Installing, deploying and activating the WISP Solutions and Features was successful. Its when you try to access any of the Citrix Administration links in Central Administration was where we had problems.

So we had to figure out a way to reveal the true error. After trawling through the Citrix Forums for several hours we came across a post which described the steps to turn on error reporting. Once we were able to see the true error, fixing the issue was easy.

Here are the steps we took to turn on error reporting in SharePoint 2007:

Locate the web.config file for the web application associated with your site.

If this is the default web application, this will be at:
C:\Inetpub\wwwroot\wss\VirtualDirectories\80\web.config

If this is for the Central Administration site then the location will be:
C:\Program Files\Common Files\Microsoft Shared\web server extensions\12\TEMPLATE\LAYOUTS

Open web.config and make the following changes:

1. Locate the <customErrors> tag and change it to:
<customErrors mode="Off" />

2. Set callstack="true" as shown below:

<configuration>
<SharePoint>
<SafeMode MaxControls="200" CallStack="true" DirectFileDependencies="10" TotalFileDependencies="50" AllowPageLevelTrace="false">
</SafeMode>
</SharePoint>
</configuration>

This will cause the actual error to be displayed, for example:

The expression prefix 'WISP' was not recognized. Please correct the prefix or register the prefix in the <expressionBuilders> section of configuration. at System.Web.Compilation.ExpressionBuilder.GetExpressionBuilder(String expressionPrefix, VirtualPath virtualPath, IDesignerHost host)
at System.Web.UI.ControlBuilder.AddBoundProperty(String filter, String name, String expressionPrefix, String expression, ExpressionBuilder expressionBuilder, Object parsedExpressionData, Boolean generated, String fieldName, String formatString, Boolean twoWayBound) 
at System.Web.UI.ControlBuilder.PreprocessAttribute(String filter, String attribname, String attribvalue, Boolean mainDirectiveMode) 
at System.Web.UI.ControlBuilder.PreprocessAttributes(ParsedAttributeCollection attribs) 
at System.Web.UI.ControlBuilder.Init(TemplateParser parser, ControlBuilder parentBuilder, Type type, String tagName, String id, IDictionary attribs) 
at System.Web.UI.ControlBuilder.CreateChildBuilder(String filter, String tagName, IDictionary attribs, TemplateParser parser, ControlBuilder parentBuilder, String id, Int32 line, VirtualPath virtualPath, Type& childType, Boolean defaultProperty) 
at System.Web.UI.TemplateParser.ProcessBeginTag(Match match, String inputText) 
at System.Web.UI.TemplateParser.ParseStringInternal(String text, Encoding fileEncoding)

David
Twitter - http://twitter.com/citrixreadiness
Citrix Support on Facebook - http://www.facebook.com/citrixsupport

Summary

Project Kensho OVF technology provides the Citrix ecosystem with excellent tools to create and consume virtual appliances based on the OVF standard.  Project Kensho OVF technology is currently available in two utilities: 

• Project Kensho OVF Tool
• XenConvert 2.0.1

This article aims to describe basic use cases of each tool and where it fits within the greater context of deploying and consuming virtual appliances using the Open Virtualization Format (OVF).

Background

Project Kensho is a Citrix Labs endeavor tasked with de-risking and improving our understanding at applying DMTF OVF and CIM technology to XenServer. 

In the case of OVF, the standard is new and exciting. Its potential to reduce costs and improve virtual machine deployment for Citrix internal and external partners and customers is enormous.  Today, it is one of the most exciting technologies in the world of virtualization.

Project Kensho OVF technology is present in both the Project Kensho OVF Tool and XenConvert 2.0.1.  Each tool is unique in how it uses OVF and its position in the user community. 

In the simplest terms, the Project Kensho OVF Tool is aimed at OVF based virtual appliance creation and consumption where as XenConvert 2.0.1 is a P2V/V2V conversion utility supporting OVF virtual appliances.

Each offers the user different paths to create, convert and import OVF based virtual appliance content into XenServer.

Project Kensho OVF Tool

First released in October 2008 as an ongoing series of Tech Previews, the Project Kensho OVF Tool targets the creation and consumption of OVF based virtual appliances. This utility is part of the Project Kensho Tech Preview suite consisting of the Project Kensho OVF Tool and the Project Kensho XenServer CIM Interface. 

The Project Kensho OVF Tool is a full featured import/export utility offering users the latest OVF capabilities. The utility accommodates both the XenServer and Microsoft Hyper-V hypervisors and has the ability to directly import VMware OVF/VMDK content without conversion.

Unlike XenConvert, the Project Kensho OVF Tool is not targeted at static file format or physical to virtual conversion.  The utility requires the user to have administrative privilege to the hypervisor.  It interfaces directly with the hypervisor enumerating VM content for export and identifying hypervisor hosts for import.  The Project Kensho OVF Tool's primary function is to manage movement of OVF packages into and out of the hypervisor.

Project Kensho OVF Tool – Appliance Creation (Export)

Virtual appliance producers have the ability to create virtual machine appliances by exporting one or more virtual machine guests as an OVF package from either the XenServer or Hyper-V host. 

OVF supports one or more virtual machines within a single package.  This enables virtual appliance producers with the ability to package entire datacenter suites into a single file.  This is very useful when distributing suites like XenApp or other multi-server products.  Currently, the Kensho OVF Tool is the only Citrix utility capable of exporting OVF content directly from a hypervisor.

When exporting the appliance, the user has the ability to embed an End User Licensing Agreement (EULA) into the OVF.  The EULA is presented during import forcing the consumer to agree or decline the terms of use of the appliance. 

For added security, the user can digitally sign the OVF file and encrypt the virtual disk content.  These features add additional value to the virtual appliance's integrity.  Users can also compress and add a file manifest to OVF package.

Project Kensho OVF Tool – Appliance Consumption (Import)

Consumers of the OVF package have the option to import the virtual appliance into a XenServer or Hyper-V hypervisor.  Among other features, the Project Kensho OVF Tool enables this process with features such as hardware mapping and integrity validation of the OVF package.

Hardware mapping eases post virtual appliance import configuration steps.  For example, a user could map the network interface card (NIC) described in the OVF to the virtual networks unique to the target XenServer. The same support exists for storage and system mapping.

One highly useful feature is the direct import of VMware OVF/VMDK content into a XenServer or Microsoft Hyper-V environment.  This capability reduces time and costs as Project Kensho implements fix up capabilities making migration of the VMDK easier and less time consuming.

XenConvert 2.0.1

As the first mainstream XenServer utility to adopt OVF, XenConvert 2.0.1 applies Project Kensho OVF technology to the conversion process.  As a Physical to Virtual (P2V) and Virtual to Virtual (V2V) converter, XenConvert 2.0.1 now gives virtual appliance users a number of options to either create OVF content for import into XenServer or convert OVF content produced by 3rd party products like VMware. 

Unlike the Project Kensho OVF Tool, XenConvert 2.0.1 does not require administrative rights to a XenServer in order to convert physical or virtual machine assets into formats compatible with XenServer.  The utility can perform its conversion functions without any XenServer interaction.  However, in scenarios where the user chooses to import into XenServer as part of the conversion process, the utility conveniently offers this capability thus requiring the user to authenticate to a XenServer with administrative credentials.

In the P2V scenario, XenConvert 2.0.1 facilitates the creation of an OVF based virtual appliance by using a physical machine as the appliance reference.  This is a unique use case as the creator of the virtual appliance now has another avenue of flexibility in determining the source of the virtual appliance.

One helpful use case is converting an existing XenServer XVA virtual disk to an OVF/VHD package.  This gives virtual appliance users the option to easily convert the XVA to a standards based virtual appliance format.

Another use case is converting from a VMware OVF/VMDK to XenServer.  Kensho OVF technology allows XenConvert to convert and import VMware OVF content into a XenServer environment.  This is very helpful when moving between hypervisors and gives users the freedom of OVF interoperability at the virtual disk level.

There are many more possible use cases employing Project Kensho OVF technology found in XenConvert 2.0.1.  XenConvert 2.0.1 supports OVF packaging options like compression, digital signatures, encryption and archiving the OVF package as well as attaching EULA information to the virtual appliance.

For use cases where P2V and V2V conversion is a must, XenConvert is an excellent tool to convert and import OVF content into XenServer.  And, it represents yet another method of creating and consuming OVF based virtual appliances. 

Conclusion

Project Kensho OVF technology offers users a variety of options whether using the Project Kensho OVF Tool or XenConvert 2.0.1.  Each utility allows creators and consumers of OVF based virtual appliances a variety of paths into XenServer creating flexibility for all users of the technology. 

By providing tools to address the conversion of physical and virtual disk formats to XenServer as well as the import and export of OVF content, Citrix is actively positioning customers and partners for the move into the virtual appliance world.

After 16 years with a Golden Retriever it is safe to say my family loves dogs.  When she went to the happy hunting ground (doggie heaven) we decided to get another.  My wife wanted a small dog so that it could live in the house and she could hold it and snuggle up.  Well, I got her a small dog... at least it was when we bought it .  He was the cutest little guy ever and weighed in at a meager 12 lbs (about 5.5 Kilos).  Unfortunately, he grew at a rate of 5 lbs (2.3 Kilos) per week after that for a long time.

It may seem like a stretch, but a lot of companies are shopping for just the right size Cloud provider to handle all of their IT needs.  On the one hand there are huge Clouds that provide a great service if you're looking for an endless amount of capacity and you have the technical savvy to create a virtual data center inclusive of applications, profiles, back-up utilities and a schema to run the whole thing.  On the other hand there are smaller Micro Clouds (another word I just made up) that will offer up services but don't look or act like their huge Cloud cousins.

The bottom line is that there are all types of companies with differing needs when it comes to Information Technology and the emergence of Clouds.  The problem is that companies who need the care and nurturing a Micro Cloud provider can offer really get confused when they go to buy a service they think will be able to cuddle up with them only to find that they have purchased a monster that is growing up to be something larger than they expected.

So what's the point of all this as it relates to my typical diatribe on Citrix Service Providers?  If you want to get into the business of Cloud provision, make sure you know what your purchasing ahead of time... otherwise you might find that what you thought you wanted, turns out to be something way more than you bargained for and you might just be spending a lot of time in the dog house feeding it!

Just like the puppy I bought that now weighs 145 lbs (70 Kilos) and pretty much rules my house!

What's new in desktop virtualization?  Well, lots of announcements from different vendors trying to peddle their wares, but I haven't seen or read anything very thought provoking. 
<rant> (Man, I'm totally geeking out here)

I'm trying to keep abreast of the latest happenings in the desktop virtualization space from a design and architecture perpsective, but honestly, there isn't much.  There are tons of solutions out there, some better than others. There are many point solutions out there that solve 1 issue for desktop virtualization.  Heck, even Brian Madden commented about the one-hit wonders in a recent blog. 

I'm also on twitter (@djfeller) and I try to follow VDI/Desktop Virtualization, I have Google Reader alerts setup (You can follow my shared items but there isn't much I've found useful). What do I typically see? One post about a new feature, then I see it retweeted a zillion times (Ok, I'm exaggerating a little, but still).  I see articles about why companies aren't doing the VDI/Desktop Virtualization thing yet.  Why? It's not because there aren't solutions. There are. They might not solve every use case, but they can solve some for some users. So what's the holdup?   No one is showing them how to get it done. 

It's time for a REAL discussion. Let's start focusing on designing a desktop virtualization solution.

</rant>

I'm not going to lie to you and tell you desktop virtualization is easy. It won't be a walk in the park unless your park is full of mountains, rivers, mosquitoes, coyotes, wolfs and bears.  So, why would we attempt to do something like this? Because the alternative is even worse. With so many different user requirements you can quickly see how the current distributed desktop environment is a disaster waiting to happen (or already happened over and over again).

But let's not dwell on the ugliness of the current model. Let's instead focus on designing a better solution.  Let's start talking about design, and my oh my there is a lot to talk about, which is why I'm about to start a blog series on designing a desktop virtualization solution with XenDesktop.  I plan to focus on the main design decision areas and giving you my thoughts and recommendations based on what I've seen so far. I'm positive many of you have seen different things, which I encourage you to comment so we all can learn. 

This should be a great series and I can't wait to hear some of your comments.  (BTW, I got a lot of great comments for all of you during our Provisioning Services for XenApp blog series and hope to get the same level of feedback.)

Daniel - Lead Architect - Worldwide Consulting Solutions
Follow me on Twitter: http://www.twitter.com/djfeller
Follow me in the Blogs: http://community.citrix.com/blogs/citrite/danielf
  

Summary

This article provides a basic overview of the Open Virtualization Format (OVF) specification as used in Project Kensho and XenConvert.

Background

Virtual Machine deployment and use has exploded in recent years. Many vendors, including Citrix, have been instrumental in the widespread adoption of virtual machines in today's computing climate. New use cases, including the distribution of virtual appliances, require a more standardized way to describe and deliver virtual machines. This article aims to shed some light on OVF as used in currently shipping Citrix products.

What OVF Is

Comprised of the Virtualization Management Initiative (VMAN), the Distributed Management Task Force (DMTF) standards body created a standard representation of virtual machine metadata named Open Virtualization Format (OVF).  OVF seeks to allow virtual machine hypervisor vendors and the users of virtual machine technology to create and consume virtual machine metadata free from proprietary formats.

Virtual machine metadata includes a virtual machine's name and configured memory as well as CPU, network and storage settings among other attributes. A standards approach to creating and consuming virtual machine metadata eases the ability to move a virtual machine from one platform to another as well as distribute virtual appliances to end users.

However, OVF goes beyond just the description and virtual hardware attributes. OVF allows a virtual appliance vendor to add items like a EULA, comments about the virtual machine, boot parameters, minimum requirements, security attributes and a host of other features.

An OVF is not just limited to a single virtual machine. An OVF can describe multiple virtual machines. These virtual machines can be packaged as a virtual appliance suite all wrapped up in a single file. Creators of the appliances also have the ability to encrypt, compress and digitally sign OVF content.

With these capabilities, there is a wide range of packaging and deployment possibilities when using features provided by the OVF specification found in Citrix utilities.

What OVF Is Not

OVF is not a specification that describes a virtual disk. To import OVF content requires hypervisor compatibility with the associated virtual disk.

For example, to import a VMware produced OVF, which includes a VMDK disk into XenServer, the user needs to convert the VMDK into a virtual disk format compatible with XenServer.. The same process is needed to import a XenServer OVF which includes a VHD into a VMware hypervisor.

To assist end users with dissimilar disk formats, Citrix provides XenConvert 2.0.1 which converts VMware OVF/VMDK content into a XenServer compatible format (OVF/VHD). The Project Kensho OVF Tool enables direct import of OVF/VMDK content into XenServer without converting into an intermediate format. Using this method, the Project Kensho OVF Tool reduces migration time by ~ 40%.

With Microsoft Hyper-V content, no conversion is necessary as XenServer natively supports the VHD format. The Project Kensho OVF Tool facilitates the import and export of OVF based VHD content for users of Microsoft Hyper-V.

OVF File Components

From a file perspective, OVF is not just one file. It is a collection of files representing everything from virtual machine metadata, virtual disks, manifests, certificates and archive files. These files can be encrypted, digitally signed, compressed and archived.

The most apparent file is the metadata file. It is an XML document that has the extension of .ovf. This file contains the metadata describing one or more virtual machines and contains the location of the virtual disks associated with the virtual machines. It also contains information about how to manage the virtual machines during import, EULA information and other capabilities described in the specification. A file of this type could appear as myappliance.ovf.

Accompanying the .ovf are one or more virtual disks. Citrix uses the .vhd format for virtual disks associated with a Citrix produced OVF. The .ovf file provides the location to one or more VHD disks. VHD disks can be relative to the OVF or can be a URL.

The OVF specification defines two specific groups of files:

OVF Package
An OVF package is a group of files required for importing the virtual machine.

• The .ovf file containing the metadata. Example: myappliance.ovf
• One or more .vhd virtual hard disks. Example: myappliance.vhd
• A manifest file describing the package and checksum. Example: myappliance.mf
• If a user chooses to digitally sign the OVF file, a certificate file. Example: myappliance.cert

OVA Package
An OVA package is a single file archive of the .ovf file, .vhd file, .mf file and, if applicable, the .cert file. The OVF specification requires an archive to be in the TapeARchive (TAR) format. TAR is a Unix derived archiving format.

• All files associated with the OVF are included in this file. Example: myappliance.ova

The OVF specification allows users to compress an OVA.

• OVA compression uses the gzip algorithm. Example: myappliance.ova.gz

OVF and XVA

OVF is the natural successor to XVA. Accompanying an XVA package is a file named ova.xml. This is XenSever's proprietary metadata descriptor. Citrix utilities like XenConvert 2.0 convert an XVA into an OVF/VHD combination. XenConvert is useful in creating distributable virtual appliances based on the OVF standard from existing XVA content.

DMTF VMan OVF Specification

There is much more to OVF than the simple description above. To learn more about it, please refer to the OVF specification on the DMTF website.

DSP02431.0.0 Open Virtualization Format Specification