Nov 14
Three Things You Should Know About VDI (Part 1)
Jason Cooper
I’ve been a C/D/H consultant for five years. I have the dual distinction of being both C/D/H’s first Southeast Michigan consultant AND our first VMware Certified Professional. Specializing in desktop management and virtualization, projects involving MetaFrame or ZENworks or VMware expose me to almost every corner of the enterprise, from messaging to networking to collaboration.
Technology is what I work at. Family and music are what I work for. In my copious spare time I enjoy gardening, camping, and cycling. I play guitar and a little harmonica, sometimes simultaneously. It occurs to me that I could duct tape a tambourine to my knee, but that would just be too weird.
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Articles by Jason Cooper
Everyone is talking virtualization. Most enterprises have adopted VMware in some form, for testing or production server consolidation. The new buzzword is VDI, or Virtual Desktop Infrastructure. (Read all about it at http://www.vmware.com/products/vdi/.)
In this model, client workstations are virtualized; meaning virtual machines are deployed as Windows workstations. Using a remote access protocol (like VNC or RDP) client connections are brokered through the Virtual Desktop Manager. A user logs into a client device (ANY client device) and accesses the same Windows desktop.
If you’ve already invested in VMware Infrastructure 3, you know the price tag can be steep. You can host up to 40 virtual machines on a single ESX server. You need a SAN or iSCSI NAS device. You’ll need network infrastructure and thin client devices. The initial cost may be greater than that of deploying new workstations. The cost justification for VDI is in the long term cost of owning Virtual Machines running your desktop operating system vs. physical boxes running it.
The purpose here isn’t to sell you on VDI, or Virtualization in general. This series of blog entries is intended to dispel a handful of misconceptions about the solution. These are based on real-world experiences and conversations with clients and peers.
First on the Agenda is your network infrastructure. The misconception: “Once I deploy VDI I won’t need nearly as many Ethernet switches or IP addresses.”
Don’t laugh. It’s REALLY bad for a consultant to laugh in the client’s face. Anyone that ever ran a thin-client device for Citrix or Terminal services sees the flawed logic in this statement.
YES, the VDI desktops connect to virtual switches defined inside of VDI. YES, the traffic between the virtual desktops and any server running in VMware is hyper-fast; it occurs virtually, not using “real” switches. YES, the network traffic being delivered across the wire is very light—basically keystrokes, mouse clicks, and video (audio, maybe…..but that’s another blog).
Not only will replacing a physical desktop with a VDI enabled thin-client not reduce the number of Ethernet ports you host, you’ll double the number of IP addresses you need. If you have 100 physical machines today that you migrate to 100 virtual desktops, the replacement thin-client devices still need a network connection and an IP address. Don’t look to save money with VDI by downsizing the number of physical ports on your network. On the up side, VDI could delay or eliminate the need for a costly upgrade to GigaBit Ethernet.
Next time, I’ll share more truths about VDI deployments, and why best practice is still best practice whether the desktop is physical or virtual.
From http://www.vmware.com/files/pdf/vdi_datasheet.pdf (VMware Virtual Desktop Infrastructure Product Data Sheet)
Update: Part 2 was published on Dec 1, 2008! (http://www.cdhtalkstech.com/2008/12/01/three-things-you-should-know-about-vdi-part-2/)
Update: Part 3 was published on Dec 12, 2008! (http://www.cdhtalkstech.com/2008/12/10/three-things-you-should-know-about-vdi-part-3/)