Virtualizing your desktop infrastructure can come with a bevy of benefits: centralizing your hardware investments and your management or allowing disparate teams to collaborate with ease. However, VDI can put a lot of strain on your other infrastructure, and if it’s not up to par, what may have been tolerable before in terms of network performance can become near unusable with virtual desktops implemented.
When we are brought into a client’s VDI project, we spend a considerable amount of time on discovery and planning just for that reason. Our VDI project plan template (without any customizations added due to customer complexity, I might add), is about 2,000 lines and almost two-thirds of that is discovery.
After discussing the reasons for why VDI is right for you, we’ll dig into the nuts and bolts. While storage performance often reigns supreme in the VDI prep discussions, verifying your network is ready for VDI is also a big part. Checking the core network health is important for nearly everything we do, but VoIP and VDI are particularly latency sensitive so we especially push this for those types of projects.
Here is what we ask our clients about their networking when they tell us they want to roll out VDI:
Is Your Network Efficiently Designed?
Are your distribution switches overloaded? Do you have enough uplinks to support the number of ports you’re offering up to clients? Overall, how far is the path your data has to travel? If you’ve got a bunch of loops or your network isn’t organized in the most efficient way — introducing lots of hops for your data to go — your latency is going to increase.
Is Your Hardware Sized Properly?
First you have to know how much data you’ll end up pushing – how many machines, how many hosts, and what the workload is. Knowing this will determine if your switches and firewalls can handle what your VDI implementation will throw at them.
For example, the popular PCoIP protocol for VDI is the User Datagram Protocol (UDP), which is extremely sensitive to latency/dropped packets. Its more reliable brother, Transmission Control Protocol (TCP), has a system of acknowledging the receipt or loss of packets. However, with UDP, typically for video or audio, replacing that lost packet later is actually detrimental to performance. You wouldn’t want one frame in a video that was lost 30 seconds ago to suddenly appear while you’re streaming, would you? It wouldn’t make sense.
In other words, if you’ve got a VDI design hinging on UDP, you want solutions that can handle that type of workload. You’d be surprised to find out how many common switches and firewalls are not spec’d out to handle UDP, so verify first. If you plan on utilizing VPN functionalities, you’ll also have to look into that and if they support UDP.
Is Your ISP Bandwidth Sufficient?
One of the popular drivers for VDI adoption is a remote workforce or remote offices. That means they all have to connect to your core via the Internet. Double check what your circuit agreement is with your ISP and then measure it against what you estimate you will be using based on your VDI workload calculations.
Rolling out VDI should be a careful process, otherwise the entire implementation will be hobbled from the get-go. Your core network is the backbone of nearly everything else you do, so be sure it’s configured as efficiently as possible.