If you were asked what desktop resources your needed how would you answer? If you ask me what type of desktop I need, I’m going to say, 2+ cores with at least 4+ GB of RAM, 500+GB hard drive, etc. If you look at what I really need, you will see 1 core and maybe 2-3 GB of RAM. In fact, when I look at my resource consumption, I get close to 2.5 GB of RAM by the end of the day due to the number of applications I have running, memory leaks in some of my applications, and applications not freeing up memory when closed.

Like me, many users only consume a fraction of their total potential desktop computing power, which makes desktop virtualization extremely attractive. By sharing the resources between all users, the overall amount of required resources is reduced. However, there is a fine line between maximizing the number of users a single server can support and providing the user with a good virtual desktop computing experience.
Improperly allocating resources to the virtual desktops is the 7th most common mistake make. Other mistakes, discussed previously, include:

10. Not calculating user bandwidth requirements

9.   Not considering the user profile

8.   Lack of Application Virtualization Strategy

One of the lessons we learned from virtual desktop implementations is trying to push the hypervisor, any hypervisor, too hard results in a poor user experience. The following recommendations help optimizing the environment by focusing on the hypervisor:

What other suggestions do you have for optimizing the hypervisor in a desktop virtualization world? I expect to hear quite a few comments, especially around memory overcommit and ballooning portion.

Daniel
Lead Architect – Worldwide Consulting Solutions
Follow Me on twitter: @djfeller
My Blog: Virtualize My Desktop
Questions, then email Ask The Architect
Facebook Fan Page: Ask The Architect

…No, I am not talking about the world-famous subway system in London, but rather like to pick up the topic by Dr. Philip Chase on the Physician’s view of an EMR. Dr. Chase describes how a recent visit to his physician revealed that the esteemed healthcare provider spent a lot of time typing Dr. Chase’s answers into an EMR application. The physician’s attention was divided between the patient and the computer system and the entire encounter had the appearance that the EMR itself interfered with the doctor – patient relationship; hence the “gap” between data acquisition and data entry.

Since there’s a lot of talk on EMR’s these days (one recent blog post describes the HITECH Anxiety), I figured it be a good time to reiterate some of the common sense EMR thoughts and best practices.
• Doctors don’t want to be IT admins. Correct. I don’t think they have to. Purely Internet-based EMR vendors use this tagline to entice providers to move all of their patient data to a hosting provider, but many physicians are more comfortable with on-premise solutions. Roughly 50% of office visits are delivered by 1-2 doctor practices. Like many other small business in all kinds of verticals, physicians can rely on other (often small) businesses in the IT / Computing world to setup a local system and support a locally running EMR. It’s “my computer guy” who takes care of installing, maintaining, patching, and backing up the systems in any small business, regardless of the industry. Action: Think about hosted vs. on-premise systems and pick the ones that you are most comfortable with.
• Usability is key. You don’t want your patients to stop seeing you, because the visits have become impersonal. Don’t focus more than 5-10% of your patient time looking at a computer screen. This will require discipline and some practice. Pick EMR software that lets you work from selection lists and templates rather than free text. Practice some typing (if that’s new to you) and have a vendor demonstrate the speed of documentation and order entry to you.
• Devices play a big role. Bigger than you think. Vendors bombard you with different options. Everything from regular office PCs, laptops, tablet PCs (including the Apple iPad), to computers on wheels (COWs) are options. Depending on your practice setup, one or more of these may fit. Here are some thoughts: Don’t set up your devices statically (that would require you to turn your back on the patient on occasion). If you go for wheeled devices, make sure they are not clumsy or blocking your space and movement in the practice. Ensure that wireless networks reach all your exam rooms and provide good signal strength. Consider a tablet device as you can carry it around. Be mindful of the device often occupying at least one of your hands that you won’t have avalailable to examine or treat the patient. Some devices with smaller form factors are said to fit in a lab coat. Try it before you buy! Consider the devices battery life and screen size. Action: Try the different devices in conjunction with the short list of EMRs you’re considering. Some vendors have specific user interfaces for mobile devices or iPads that improve usability when using a multi-touch interface.
• Multi-user environments pose special challenges. If you have more than 1 clinical user or running a group practice, consider the fact that physicians will physically move away from a device and into the hallway or next exam room. Unless you choose portable devices, consider fast log off and log on modalities and session roaming. The latter can be achieved through application and desktop virtualization, where your application executes centrally and the “terminals” in the exam rooms and hallways just provide interactive access to the application.
• Offsite usage. Nothing is more annoying than not having access to a system when you need it. Ensure that your system has secure offsite access built in. In most web-based EMRs , you should be covered. More elaborate systems may require app or desktop virtualization where the apps and data stay securely tucked away in the data center (or data closet, depending on your size) and allow your users to connect securely over the Internet to the user interfaces of the apps. Action: Discuss those options with your “computer guy” and your EMR vendor.

I plan on sharing more specific virtualization best practices with you in the upcoming weeks and months. Please let me know if there are specific topics you would like to hear about.

Florian
Twitter: @florianbecker
Ask the Architect – Everything Healthcare
Tech Target Blog – Virtualization Pulse

Once upon a time, there was a little school (70,000 users) with a  little problem (desktops over 5 years old) with a little idea. The school was trying to find a way to do more with the tax subsidies. The desktop environment was becoming ancient. The newest desktops were 5 years old with many more approaching 10 years.  And because the district consisted of many different schools, there was little similarity. There were different endpoints, different applications and even different quality of service.  With so many students having home PCs, the school was also interested in allowing these students to work with their applications while not at school.

The school decided to try something new… desktop virtualization.

But if you had to create a desktop virtualization design for a school or your organization, how would you begin? What would you focus on?  What do you think are the most important design components?  That is what we will focus on during a Ask the Architect TechTalk on June 18th at 1PM Eastern time.  Not only will we focus on the hypervisor, which is Microsoft Hyper-V, we will also focus on the three Citrix FlexCast models used, the image delivery solution, applications integration and how the XenDesktop farm is designed.

There will be many interesting points throughout the TechTalk including this one: To help save money, local Hyper-V disk drives will be used for the virtual desktops instead of more extensive SAN storage. I’ve spoken about this in a previous blog and this design puts it into effect.

Still aren’t convinced that you should tune in? Then how about looking at these tidbits for the environment.

• Hyper-V Servers for desktops: 300
• Hyper-V servers for infrastructure components: 8
• Provisioning Services servers: 8
• Blade PCs: 500
• Shared Storage: 300-700 GB
• Number of desktop images: 5

Still not convinced? Then how about taking a look at the ABC School District design document. You can also read about some of the design considerations for this organization in these blogs:

• Overview of the ABC School District
• How many images do i need
• Choosing the correct FlexCast model

Don’t forget to register and I hope to see you there and hear some great questions.

Daniel
Lead Architect – Worldwide Consulting Solutions
Follow Me on twitter: @djfeller
My Blog: Virtualize My Desktop
Questions, then email Ask The Architect
Facebook Fan Page: Ask The Architect

“When angry count to four. When very angry, swear”.  The wonderful words of Mark Twain. Based on this quote, I know of many users who are very angry because of all of the swearing. It is crazy how one failure in the environment can cause so much distress.  How forgetting one design decision can cause so much negativity towards IT.Not only that, forgetting to create a profile strategy can bring a virtual desktop project to its knees. Take the following, real world scenario, as an example:

An organization had a profile strategy in place.  Users started working in the new system. One day, a user had a profile corruption issue. To solve the issue, the profile was deleted.  This meant the user had to recreate their entire personalized environment. After the profile was deleted, the user quickly noticed all of their documents were deleted.  Upon closer inspection, the user stored their documents in the “My Documents” folder. When the profile was deleted, the My Documents folder was also deleted.  Can you say Bye Bye data?  Bye Bye 3 weeks worth of work.

Not convinced that profiles are important, then let me give you another example (You can’t make this stuff up):

An organization was running a hosted VDI desktop solution for a few months and decided the profile solution required modifications.  Upon the updates, every user lost all of their personalization configurations.  NOOOOO

The user’s profile is one of the major ways the pooled virtual desktop becomes personalized. Forgot about virtual desktops for a moment. The user profile is important for traditional desktops. If users are going to accept a new desktop strategy, they must have the ability to personalize their desktop environment. Personalization enhances the computing experience and oftentimes makes users more efficient. When organizations do not properly plan the profile strategy, one or more of the following will likely happen (as can be seen in the previous examples):

• Slow logon/logoff performance
• Inconsistent results
• Lost settings

These challenges will result in a negative perspective of the entire solution.

To overcome these potential challenges, a profile strategy must be put into place that includes items like:

• Folder Redirection: Have portions of the profile stored on a network drive outside of the roaming profile. This allows the profile to load faster and protects these items from profile deletion.
• Group Policies: Utilize group policies to configure the user’s virtual desktop profile. These policies should only be used when the user logs onto a virtual desktop.
• Persistence: Utilize a profile solution that allows for the extraction and storage of the personalized components of a user’s environment outside of the profile. I’ve seen many organizations have great success with Citrix Profile Management as well as AppSense Environment Manager. I’m not going to go into details of these as you can simply click on the links to find out more.

The point is that it takes users a long time to get their environment configured in just the right way.  Loosing those settings is basically like telling the user they don’t matter.  If this happens to many times, you’ll end up with user riots. I’ve seen many users get really angry when talking about their profile and the issues they have.  I’m glad I wasn’t responsible for the mess.

What other profile strategies have you seen that works as well? Any specific settings you recommend? Any tools?

Don’t make this dreaded profile mistake or horrible bandwidth mistake, which i spoke about previously.

Daniel
Lead Architect – Worldwide Consulting Solutions
Follow Me on twitter: @djfeller
My Blog: Virtualize My Desktop
Questions, then email Ask The Architect
Facebook Fan Page: Ask The Architect

One of the main goals with desktop virtualization is to reduce the number of required desktop images. The fewer number of images, the easier it is to support and maintain the desktop environment, which makes desktop virtualization so promising when compared to the traditional desktop approach. The goal is a single image, but oftentimes, other factors play a role in slightly increasing that number. Take, for instance, the ABC School District Reference Design.

 The design called for 5 different desktop images, as shown in the figure.

 
If you look at the specifications, many of the configuration details are identical. So why create different images for different user groups? It really came down to future plans. The ABC School District decided that it would be easier to design the environment with unique images for the different areas:

• Middle School
• High School
• High School Blade PCs
• Teachers & School Administrators
• Support Staff

Ideally, we probably could have reduced the number of images, with the aid of application virtualization. But the school district wanted to make sure unique images were available if certain applications were later identified to be incompatible with the different forms of application virtualization (application streaming and application hosting). Also, it would have been possible to integrate the High School and High School Blade PCs images into a single image, but because the Blade PCs are delivered without a hypervisor, there would be variations in the device drivers (something Provisioning services can easily handle). To make the management of the images easier, it was determined to separate these images as well.

So we are left with 5 images. Not bad for an environment with 20,000 end points.

Daniel
Lead Architect – Worldwide Consulting Solutions
Follow Me on twitter: @djfeller
My Blog: Virtualize My Desktop
Questions, then email Ask The Architect
Facebook Fan Page: Ask The Architect

Do you ever wonder how much bandwidth you need to do a desktop virtualization implementation? Regardless of the flavor of virtual desktop being implemented (hosted shared, hosted VM-based VDI, local streamed, etc), the network plays a critical role. That should not be surprising (if it is, we need to have an even bigger discussion). If you don’t plan your network bandwidth appropriately, you will have unhappy users, who will make you unhappy.

As we would expect, the user experience degrades as the latency increases and the bandwidth decreases. Proper network planning must be based on the type of work users are performing and the overall network topology. Back in the XenApp-only days, many people used 20 kbps as an estimate for network bandwidth requirements. Can we use that for virtual desktops? NO (although I could configure XenDesktop to only use 20 kbps).

Virtual desktops require more bandwidth because:

• In default configuration, virtual desktops provide a greater and richer experience than the default XenApp configuration.
• Virtual desktop users are idle less often than hosted application users. For example, if a user is sitting in front of a workstation and is accessing a hosted application on XenApp, the desktop and XenApp applications both appear as active. However, when the user is not working with the XenApp application, they are identified as idle by XenApp even though they might be active on their desktop. Due to this difference, the desktop will have less idle time than XenApp hosted applications.
• Desktops access and consume more multimedia and graphical mediums than most applications. A user’s desktop session also includes internet activity, which often includes more graphics, video and sounds. When using a XenApp hosted application, these multimedia activities are only utilized if the application allows.

Estimating network impact is not a trivial matter because the ICA/HDX protocol tunes itself based on the amount of bandwidth available. The less bandwidth available means more compression is applied. Also, any estimate must include percentages for different user activities: typing, graphics, Internet, video (Flash, WMV, etc), and printing. With this information, the following table can be used to create an ESTIMATE (and I do mean this is an estimate):

 
By calculating the percentage of time a user is expected to be doing certain activities, a rough estimate can be determined for HDX bandwidth requirements. If multiple users are expected to be accessing the same type of content (videos, web pages, documents, etc), integrating the Branch Repeater into the architecture can drastically reduce the amount of bandwidth consumed. However, the amount of benefit is based on the level of repetition between users.

Note: Additional details on the bandwidth estimates can be gathered by referring to the following Citrix white paper: CTX124457 – Performance Assessment and Bandwidth Analysis for Delivering XenDesktop to Branch Offices.

So what does this mean? It means using a single number as your bandwidth estimate is not good enough. You need to understand what users are doing and what percentages you expect them to be doing different activities. After that, you will get a good idea of how much bandwidth is required for a virtual desktop implementation.

Daniel
Lead Architect – Worldwide Consulting Solutions
Follow Me on twitter: @djfeller
My Blog: Virtualize My Desktop
Questions, then email Ask The Architect
Facebook Fan Page: Ask The Architect

From the words of Ralph Wiggum, I Choo, Choo, Choose You [to be my FlexCast model].

Choosing the correct FlexCast model always leaves people wondering if they made the right decision.  The answer to this question requires us to look closer into the user requirements.  For example, the ABC School District Reference Design was recently published, and as can be expected from the title, it is based on a large school district (70,000 total users, 20,000 concurrent).  How did we decide which FlexCast model was most appropriate?

It came down to simply meeting the needs of the school and the students.  This particular example used three FlexCast models:

1. Hosted Virtualized Applications: The elementary school children typically required a single application for their current class. When that particular class ended for the day, there was no need for the children to get back into the application from a different location.  Providing a single hosted virtualized application provided the easiest user experience for the elementary schools.
2. Hosted VM-Based VDI Desktops: Middle and High School students utilized many more applications, many of which were launched simultaneously. The students were familiar with a desktop interface and it was determine providing them with this experience would provide the best environment from which to work. The decision between hosted shared and hosted VM-based came down to a question of security. The school district felt it would be safer to create VMs for each desktop as opposed to the shared model.  The shared model could allow a student to cause mischief on the server, thus impacting other students. Many of the students are extremely smart and computer experts, so it was a matter of time before they breached the system.
3. Hosted Blade PCs: A small group of high school students took part in the CAD classes.  The CAD application used, and the projects students had to complete, required specialized hardware.  The school district decided it was easier to centralize a group of Blade PCs and allow students to connect as needed. This allowed for centralization and helped reduce the over number of powerful desktops required as they Blade PCs could be shared between schools.

As we know, there are more than three FlexCast models, but the School District did not have a need for them all.  In fact, as other organizations start to assess and design their virtual desktop environments, they too will see that certain FlexCast models do not fit in with the overall goals.

How does one determine the best approach? By understanding the user requirements, the limitations of each model and selecting the most appropriate model that gets the job done at the lowest cost.

Which models have you seen the most of so far?

Want to learn more about the ABC School District, then join the live webinar on June 18th

Daniel
Lead Architect – Worldwide Consulting Solutions
Follow Me on twitter: @djfeller
My Blog: Virtualize My Desktop
Questions, then email Ask The Architect
Facebook Fan Page: Ask The Architect

A long time ago, in a blog far, far away, I asked a simple question “What virtual desktop design topics are you interested in?”  Thankfully, I got a few comments from Steven Hunt, Faisal Iqbal, and Tyrone Thomas so I won’t be forced to deliver a standard, glossy marketing presentation.

Instead, those of you attending the “Designing an enterprise-class XenDesktop solution“, which will be presented by myself and Doug Demskis, will get to experience a low gloss, high value session. Doug and I have gathered mountains of feedback from our Citrix consultants and tried to condense it into 90 minutes, which in itself is no small feat because we all know how much consultants like to talk.

A few of the items we plan to cover are

• Why change XenServer’s Dom0 RAM allocation
• Recommended specs for a VMware  configuration
• Sizing guidelines for Hyper-V
• What types of disks to use
• How to calculate your IOPS requirements
• Recommendations on how to manage your desktop images
• Estimating the size of your write cache
• How to determine your Provisioning services recommended specs

This is only a portion of what you will learn in the Synergy session.  Doug and I have been digging deep into the inner workings to provide you with the best practices for your XenDesktop environment. Hope to see you there.

Daniel
Lead Architect – Worldwide Consulting Solutions
Follow Me on twitter: @djfeller
My Blog: Virtualize My Desktop
Questions, then email Ask The Architect
Facebook Fan Page: Ask The Architect

The iPad was released, and people were happy.

People brought the iPad to work, and users were excited.

Users connected the iPad to the corporate environment and IT got scared.

If you went to the Apple store and did a demo of the iPad, you might have noticed the installed Citrix Receiver (honestly, did anyone actually demo these things before buying? I bet most of us just bought it without playing around with it). But, let’s say you did demo and you selected the Receiver, what would you have seen? Windows Applications.

Yes, Windows Applications on the iPad.  I admit, that is pretty cool. In fact, why not put Windows 7 on the iPad.  It is possible. I’ve also seen reports that people are now using the iPad at work, although right now it is for minor tasks, but this will only increase.  Chris Fleck recently posted a blog talking about some of the top business use cases for the iPad.  These are great ideas, but before our employees start using a virtual Windows 7 XenDesktop desktop on the iPad for work, we need to get the environment prepared.

These items are HOT.  And you know what happens to new technology? It gets stolen. It gets hacked. First, let’s make sure our environment is secured. Second, let’s give the user the best experience.

To secure the environment, there are a few things that should be done:

1. Require authentication. Seems pretty obvious, but you can connect to virtualized applications and desktops with anonymous accounts (there are business reasons why, but this is not one of the).  If the iPad is stolen, the thief can only see the Receiver, but cannot log in.
2. Enable encryption: Citrix can encrypt the communication between the iPad and the virtual desktops/applications with RC5-128bit encryption.  As users will connect over any number of wireless networks, it is recommended that the communication is encrypted from prying eyes.
3. Disable device mapping: Although some of local iPad objects cannot yet be seen within the virtualized desktops/applications (drives, clipbard, etc), it is recommended to still disable  these features from within the XenDesktop/XenApp farms as a precaution.  The Receiver will go through updates and will add new functionality. You, as the administrator, don’t want to be surprised when users start copying materials to/from their iPads.

By doing these simple items, we can make our iPad connections to Windows 7 desktops and Windows applications more secure. But how do we make the user experience better?  Here are some recommendations:

1. HDX: Many users will browse web sites on their iPads.  By enabling HDX browser acceleration, we can compress the images and give the user a faster browsing experience.  Also, because the iPad does not support Flash natively, by accessing a hosted browser, users can view websites with integrated flash content. By enabling HDX Flash (Server-side rendering), we can allow users to view flash animation content at reasonable performance levels by slightly degrading the flash quality.
2. Visual Effects: Windows has many features that provide an interactive experience, but some of these items require additional bandwidth.  For iPad users, it is recommended to disable menu animations and to disable window content while dragging.  This allows the desktop to have faster response times.  Although we can also disable the user’s desktop background, I prefer to keep the backgrounds enabled. Hey, it’s the first thing the user sees that helps create that personalized environment.
3. Audio: Although we can disable audio, that really diminishes the user experience, especially if we are using a hosted browser so users can access flash content.  Let’s keep audio enabled, but only provide medium sound quality, which will give better performance.

The last thing we must be concerned with is that these settings do not interfere with other users. Not everyone is going to have an iPad.  Even iPad users will still access their virtual desktops/applications over other devices.  We don’t want these security/optimization settings from impacting others.  In order to accommodate iPad users, we need to create a policy with all of these settings and apply the policy to only iPad devices. By filtering on the client name of iPhone* and iPad*, we can accomplish just that.

Remember, it’s a balance between providing an acceptable user experience, while allowing for performance and security.  By tweaking the policy we can provide. So before your first user tries to use the iPad on your XenDesktop and XenApp environments, better get your infrastructure ready. No matter what you do, users will start to use their iPads to change how they access their applications. They iPad might even have an impact on what devices they use to do their work.  To get ready, you need to prepare and secure your environment appropriately.

Lead Architect – Worldwide Consulting Solutions
Follow Me on twitter: @djfeller
My Blog: Virtualize My Desktop
Questions, then email Ask The Architect
Facebook Fan Page: Ask The Architect

Fill in the blank if you will.  There are many people who are super excited about the upcoming release of the latest tablet PCs (iPad, Slate, etc).  I recently received a comment from someone on Facebook related to a previous blog saying that the iPad Will Not Replace Your Desktop.  The comment basically said
 

Does the iPad and like devices need to be fully functional to be successful?  How many people have more than one mobile device like a laptop and a netbook?”

 
That is an interesting question.  But I’m starting to wonder if we need a laptop and an iPad?  Do we need a laptop and a netbook?  Depending on what you do, the iPad or the netbook could potentially replace your laptop.  As I see it, most users have a smartphone and a main work computer, for many that is a laptop because they require a larger form factor device while not in their office.  But what if we did the following:
 
•    Main computer: Thin client
•    Mobile computer: iPad/Netbook
•    Ultra-mobile computer: Smartphone
 
If we have Citrix Receiver on all of these devices, we access the same applications/data/environment.
 
Think about all of the problems we hear about with laptops: stolen, dropped, lost, expensive, etc.  If we went down the virtual desktop route, stolen, broken or lost laptops would not be a problem because your data would be in the data center with your virtual desktop.  So why use a laptop?  
 
Is it possible that tablets and netbooks could mean that those of us with laptops can toss them away?  If the tablets/netbooks provides us with a connection to a virtual desktop from anywhere, why would we need the laptop functionality?
 
Of course this won’t work for everyone. Some people will need a laptop. But what we will see in the coming months/years is a much more diverse end point environment. We know this is coming, so it is  good idea to start planning how you will integrate all of these endpoints into your infrastructure while still trying to keep the environments secure.

Daniel

Lead Architect – Worldwide Consulting Solutions
Follow Me on twitter: @djfeller
Blog for Next-Gen Desktop: Ask The Architect
Questions, then email Ask The Architect
Facebook Fan Page: Ask The Architect