Application virtualization is becoming increasing popular. Many vendors are releasing, or have released, application virtualization utilities. Microsoft has SoftGrid, Altiris has SVS, and Citrix has their Application Streaming Client. Application virtualization can be used in conjunction with other technologies such as Citrix XenApp / Terminal Services, Citrix XenDesktop / VMware VDI, or simply workstations you may already have rolled out to your end users, especially Windows Vista.
We’re going to focus on VMware ThinApp and Citrix XenApp, but these benefits would also be applicable to a virtual desktop infrastructure as well.
First, ThinApp applications require no agent software to be installed, can run without administrative permissions and can run from any network share so it’s easy to maintain.
Second, ThinApp’s virtual OS (VOS) consumes little system resources. In fact, the VOS should consume no more than 400k of disk space or 2mb RAM per each instance running, thus keeping the majority of system services free for Citrix processes.
Third, ThinApp runs entirely in User Mode, there are no kernel mode components/device drivers. This provides a multitude of system stability and security benefits, in that it reduces the impact of any performance issues or security breaches. This concept should be familiar to Citrix Administrators, especially when thinking about user and kernel mode printer drivers. If there is a problem with a user mode printer driver, a specific print queue is affected. If there is a problem with a kernel mode driver, the print spooler service typically crashes, disrupting printing for each user connected to the Citrix server.
Fourth, you don’t install applications on the Citrix server, you merely publish the ThinApp packages. This, in effect, eliminates application conflicts! It eliminates “DLL Hell”! This is so exciting! You don’t have to worry about the consequences of installing ApplicationB when ApplicationA is already installed. You don’t have to worry about the impact on ApplicationC when updating ApplicationD. Multiple versions of applications, such as Microsoft Office, can be virtualized and published on the same Citrix server so easily, and they won’t fight with one another. I could go on and on, but I hope the point has been made.
Finally, virtualizing your applications with ThinApp will reduce application rollout time, the cost of maintaining your Citrix servers, and will likely reduce the number of Citrix servers you require. By eliminating the application “drag” on the Citrix servers, the majority of system resources are free to service end user connections, thereby increasing the number of ICA connections supported by each server.
I encourage each of you to consider application virtualization to build a high-performance Citrix Server Farm.
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Have you actually tried this?Have you succeeded in content redirection with when publishing a ThinApped application?
Thinapp should not be necessary in a Citrix environment. Citrix already offers application deployment in isolated environments. It’s the same thing and we don’t have to pay more for thinapp (Citrix installation manager is only for XenApp Enterprise edition I think).
I would tend to disagree with Matthieu.Having been a Citrix consultant for more than 10+ years, I truly dread using Application Isolation Environments for the very reason that they are a “hit-or-miss” technology which works only about 50% of the time (and I’ve been using them for as long as they’ve been available).Citrix Application Isolation Environments:1. Are only available on Citrix Servers2. Require the application still be installed to the Terminal Server / Citrix Server3. Do not generally work for same applications of different versions (even though Citrix says so).4. Updates to applications using AIE still require the server be taken offline as the applications are still directly installed (and therefore linked) to the OS.5. Citrix recommends uninstalling/reinstalling XenApp when imaging a TS. This negates the use of AIEs when needing to install an application into an AIE.With ThinApp, I can package the applications I want, build up a clean TS with or without Citrix (depending upon how I want to image/build the servers), and run all of the apps from either the local TS drive or a network drive (including publish the ThinApped apps). I can even update any of those applications using ThinApp’s Side-by-Side updating feature while the servers are all online AND the application is in use!I can tell you, had I known about ThinApp (or previously ThinStall) 5 or 7 years ago, I’d have been able to do those massive server farm builds and get every single one of the customer’s 1000+ crappy in-house built applications a built and running in a single farm without having to silo off a couple of Citrix servers for those apps that didn’t play well with other apps.Add to that the A.D. group validation logic and ability to assign apps per user or per machine via a login script is simply beautiful.In regards to Conne’s post, yes, I’ve tried content redirection as well and yes it works so long as you register the application to the machine instead of the user (simple ThinReg switch).In my mind, Citrix + ThinApp is a no-brainer.That’s just my opinion, I could be wrong.🙂
I like ThinApp packages because they have many uses outside TS/Citrix. They can be used with your current desktops, in a virtual desktop infrastructure using VMware VDI or Citrix XenDesktop, and (selfishly perhaps), and there’s no client or server (save for the space to hold the packages) required. I think I would try to use Citrix Application Streaming before using the isolation environments. My luck with those has been about the same as squidlyman.Thanks for taking the time to read these posts, I do appreciate it and always enjoy listening to the thoughts and opinions of others.
Squidlyman, I think more that I’m wrong and you’re right … 🙂
…. Multiple versions of applications, such as Microsoft Office, can be virtualized and published on the same Citrix server so easily….
not working, i really make lab on this, i make a firefox 3.0.1 and firefox 3.5.6 package
then
i run 3.0.1 on client, it works.
then i run 3.5.6, a new windows of 3.0.1 created
if i run 3.5.6 first, the second one also 3.5.6
backgroud:
profiler(XP sp2),client(XP sp2),xenapp server(server03 sp2) also in vmware station7
stream to server – fail
stream to client – fail
How does content redirection work with this?