Client Roaming in Application Virtualization 4.5 (Softgrid)
Coming from the days of implementing Softgrid versions pre-4.5, there were complications to setting up Softgrid in a large scale environment. The infamous ability in Softgrid to allow roaming users in all parts of the globe to receive their assigned applications instantly on any computer at login was an big sale among many organizations. But when deploying it, there was much work entailed to accomplish it. How do you control all these applications from streaming across your WAN links? How do I lock it down to pull from local server resources? Let me explain the progression of the versions here:
Pre- Softgrid 4.5:
In versions 4.x, Softgrid was great in centralized environments with high bandwidth availability. But in most large environments, there are branch sites you need to plan for. So where does the client stream the SFT file from? If the client is in Site A and moves to Site B, does it pull the package from Site A still? These are all sore questions to answer during your planning stage. There are different techniques to use to pull locally.
DNS- In DNS, there is a setting called Netmask ordering. It allows clients on a local subnet to pull from a local resource by giving the client the nearest IP for that subnet. So with multiple DNS host entries named "SGserver" pointing to each of the branch VAS IP's, a client when looking for SGserver would receive an answer for it's local subnet IP. This works great but their are some gotchas with clients caching the last subnet after it has moved though.
DFS- Using DFS, you can also get around where clients pulled their content from local DFS locations. Using this method, you need to have all of your AD sites and services Subnets defined. Plus you need to have separate AD sites and services setup if multiple domains. (with one domain and using windows 2003 global catologs, there really is no need for all the setup anyway's)
Softgrid 4.5:
Now we have some scalability choices that we did not have before. Here's some of these new changes:
ASR- Application source root is a big addition to the 4.5 version that allows direct manipulation on where a client streams the SFT from. It's a registry key that can instantly override the HREF path specified in the OSD. So for this, use the provided administrative template (w/RTM) to set the ASR in a GPO at the site level. So when a computer moves around and starts up, it'll receive an ASR path through the GPO to the local content location. Love this flexibility.
OSR/ISR- Like the ASR, these can be set for the ICO/OSD files as well. During EACH DC refresh, the client pulls all the ICO/OSD files down which could very well be from across the WAN. So if a user clicks the reload/refresh button 10 times and he has 20 virtual apps assigned, it can add up against your traffic. So now you can also control where those ICO/OSD files are brought down from.
ConfigMgr R2- With this new integration, Softgrid works off the backbone of ConfigMgr's enhanced scalability features. This has really become a solid solution for folks wanting Softgrid and have ConfigMgr in place.
- When a user clicks an icon file to stream a virtual application, the v-launcher or interceptor talks to the Advanced client which from it's management point, receive the location of the closest virtual enabled distribution point with that SFT and streams it from there.
- Since ConfigMgr now included 'Branch office' distribution points, a windows client can become a Softgrid storage point when no servers are available. Thus, clients at these serverless locations can also pull virtual applications within their own subnets.
- Lastly, with ConfigMgr's ability to deploy applications via the internet when in it's Native Mode (PKI certificates), this also includes virtual applications. The streaming delivery would not be able to work in this scenario, but a download and execute local delivery would allow these virtual applications to deploy, even if the user is connected at a Starbucks.
So as you can see, there are new options that help make this product more enterprise ready. I'm looking forward to implementing 4.5 with these new scalable enhancements to achieve a more dynamic solution.
Troy