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Too many enterprises leap into virtual desktop infrastructure only to find that they've bitten off more than they can chew.
Virtual desktop infrastructure (VDI) promises a lot to the admin -- easier endpoint updates, simplified antivirus and dramatic hardware expenditure reductions. But why are VDI problems -- storage usage skyrocketing, users in an uproar -- so common?
When VDI goes wrong
We couldn't resist sharing this description of the wonder -- and disappointment -- of VDI projects, as presented by Matt Allen, senior QA engineer at Tintri Unidesk, during a Connecticut 2013 VMUG meeting:
This is how VDI projects usually go: The pilot is exciting and good. Then, not all the applications can be virtualized, especially not the advanced ones. VDI performance is slow. There's not as much freedom as you thought. Difficult apps are pushed into gold images; the gold image swells. To appease various users, you create many gold images, which leads to sprawl. Suddenly, you're managing a bunch of updates on a bunch of gold images, and you end up with persistent desktops.
Don't say we didn't warn you. Luckily, VMware View veterans have tips for VDI newcomers who want high performance and user freedom right out of the gate.
Ways to do VMware View right
In response to SearchVMware's VMware View best practice tips, reader Jean-Pierre Clauws, managing director and owner of Integrated Quality Networks NV in Belgium, shared some of his own tips for a successful VMware View setup.
Storage. "Even with thin provisioning and linked clones, you can easily overcommit your storage environment. Make proper calculations," Clauws said.
Storage miscalculations are a leading cause of VDI problems, because virtual desktops use storage differently from virtual servers; they tend to be more dynamic. Many enterprises turn to solid-state storage or other hardware options to handle usage spikes. In View 5.1, VMware introduced Storage Accelerator to wield deduplication and software caching against usage spikes.
Clusters. "I always separate my environment in three clusters -- management, servers/production and View," Clauws said.
Clusters create a boundary around virtual machines and allow hosts within the cluster to trade off VMs when they need to balance resources.
Networking. "I am not using VLANS but separate switches to achieve my implementations," Clauws said.
Networking is a crucial part of View setups as users and their desktops are separated by the network. View delivers those desktops over VMware's remote display protocol, PC over IP, so latency and bandwidth will directly affect VDI performance. Virtual local area networks (VLANs) help manage load balancing and bandwidth allocation, but admins can adjust transmission limits and buffers at the switch level to maximize bandwidth and minimize latency. VMware notes that "congestion avoidance algorithms" that balance network traffic can cause packet loss that degrades View performance.
Troubleshooting. "Use vCenter Operations [vCOps] for View and monitor it very carefully in the first weeks of your deployments," Clauws said.
A major VDI problem reported by end users is boot storms, also known as login storms. Depending on how IT migrated from traditional PCs to View virtual desktops, boot storms could take place in the morning, at noon or in the evening. VMware vCOps is an optional add-on for View, loaded with several dashboards and the ability to create custom dashboards. Admins can quickly fix VDI problems that vCOps discovers with data from the View Connection Server, the View Events Database and desktop VMs.
Profiles. "Try to use as few GPOs as possible," Clauws said.
Group policy objects (GPOs) can drag out VDI login times, a problem exacerbated by Microsoft's Roaming Profiles. Clauws prefers View Persona Management, which streams user profiles from the network to the user's desktop instead of downloading all the user's files at login.
Graphics. "For 3-D experience, I've already used the HCL-compatible accelerator cards in the View servers," Clauws said. "Not cheap, but to be considered for rich CAD experience."
End users working with video or images always require special IT attention to support their processing requirements. Many VDI adopters find that graphics-intensive applications wreak havoc with virtual desktops. VMware lists graphics accelerator cards in its Hardware Compatibility List for VMware View that, along with software-based graphics accelerator tools, can allow even graphics-heavy computer-aided design users to get solid virtual desktop performance.