BACKGROUND IMAGE: iSTOCK/GETTY IMAGES
Citrix has had application publishing in its product arsenal for many years, and lots of IT shops find it very useful. Now VMware is trying to level the playing field with Horizon 6 RDSH.
One of the features in VMware's Horizon 6 product is the ability to publish applications, rather than full desktops. IT administrators usually use application publishing to deliver line of business (LOB) applications to users' PCs -- and even mobile devices -- from the data center. But no matter why you might choose to publish applications, it is important that the process be simple and manageable.
In-house-developed LOB applications are often complex. They can have multiple software components, and they are sometimes difficult to install. These applications also tend to need frequent updates, which makes new version deployment a regular challenge. In addition, many client/server applications are not well optimized for use over a wide area network; developers tend to assume that a high-bandwidth, low-latency network joins the application to its data, but that's not always the case in reality.
Why are published apps good for mobile devices?
Stripping the desktop OS away from an app improves its usability on a mobile device. A full Windows desktop is not suited to a mobile device because smartphones and tablets display a single app in full screen. But removing the Start menu navigation and window management immediately makes the application more mobile-friendly. Application publishing gives users just the applications they want on their mobile devices. An LOB app is unlikely to be optimized for a touch device or a low-resolution small screen, but the fewer layers of non-mobile interface that can get in users' way, the better.
Using a set of Windows Servers as a Remote Desktop Session Host (RDSH) farm allows users to access the application remotely. It runs and receives updates in the data center, even though user access is remote.
Using RDSH also reduces the number of copies of an application that admins need to update because the apps don't need to be installed on every PC. Keeping the RDSH hosts in the data center also makes updating apps easier because the applications live on a fast network and are always connected, unlike laptops or PCs at branch offices. And with Horizon 6 with View, you can deliver applications alongside VDI desktops using the same access infrastructure and clients.
Horizon 6 RDSH: How it works
Setting up a published application in Horizon 6 is straightforward. You need an RDSH farm -- a group of RDSH servers that all have the same configuration. You can only publish applications that are installed on Windows Servers with the RDSH role. Applications installed on Windows desktop virtual machines (VMs), such as those running Windows 7 or 8, are exempt from publishing.
Select published applications from the list of applications already installed on the RDSH servers, then assign them to users. The applications appear as icons in users' Horizon View or Horizon Workspace client, alongside any desktop pools the user is entitled to access. In the View client, applications appear with the application icon from the RDSH farm, and users can tell if they are accessing a desktop or just a single application.
What's missing from Horizon 6 RDSH?
VMware has not given us a way to manage the software installation on the RDSH hosts, but hopefully there is some work to bring the linked clone methodology to RDSH servers. This would allow you to update a master RDSH VM, then deploy its updated state to multiple RDSH servers in the farm.
Having a way to make all the servers the same is an important part of building large RDSH farms. For now, customers will need to use another Windows configuration management tool, such as System Center Configuration Manager (SCCM), to make identical RDSH hosts. You can use SCCM to deploy new RDSH severs as application load climbs, and you can use it to update the installed applications across the RDSH farm.
VMware has also yet to offer a simple way to integrate the published applications into a user's PC. Having the application appear on the Start menu of Windows client devices would simplify user education. Requiring a user to sign in to the Horizon client to launch applications works for existing View users because they're familiar with the process, but a simplified method to connect to published apps would be beneficial for new deployments.
Horizon 6 RDSH to lack built-in profile management