Wednesday, December 9, 2009

Using USB dongles with ESX-based virtual machines

The post where I mentioned how I made a pool of external fax modems work with ESX guests using a Digi PortServer has proven to be one of the most popular of my blog.

Recently, I've been faced with a similar challenge: Is it possible to virtualize Windows servers which host software that requires a copy protection USB dongle? The answer is yes!

Since I was a happy camper with the PortServers, I once again checked what Digi had to offer and found their AnywhereUSB line of network-enabled USB hubs. Simply put, these devices work like this: The hub has a LAN port, and you can use it to access USB devices through your LAN. You simply need to add a special driver to your Windows server that will "fake" a local USB port, while in fact it redirects the traffic to the remote hub. This works flawlessly with physical servers and most importantly VMs, and you can VMotion them around at will.

Digi has written a concise whitepaper that describes how to connect the Anywhere USB to VMware ESX guests here: http://www.digi.com/pdf/wp_ESXServer_AnywhereUSB.pdf. The setup is done within a matter of minutes.

The 2-port version, according to Digi's online store has a list price of 287$USD while the 5-port version is 349$USD.

But whatever you do, don't do the same mistake I did and buy a 5-port hub, thinking that each independent port can be shared among multiple servers in the same manner like Digi's serial servers can - I found out that the Anywhere USB can be connected to only one server at the time. The whitepaper above claims that you can have "multiple USB hubs per virtual machine", but don't confuse this with "multiple virtual machines per USB hub". I don't think the 5-port version is very useful for many cases unless you need to plug a lot of devices on the same VM.

Also, remember that the hub only has a 100Mb/s connection and will downgrade USB 2.0 devices to work at USB 1.1 speed. This is fine for many cases such as with a dongle, but any use requiring a high-performance data rate will be better served by using a physical server.

The fact that you can't share the hub with multiple VMs is a serious design limitation that will require you to deploy a lot of these devices if you ever need to virtualize dozens of servers that use dongles. The 287$ cost for each VM has to be considered in this context, but compared to having to install and manage a physical server, this is as cheap as it can get.

O.

Update Dec 10th 2009: I found another product that is a lot cheaper than Digi's. While it would do the job in a SOHO environment, it's built by a vendor that I wouldn't trust for enterprise systems. At 287$, better buy yourself peace of mind, and especially long-term support.

4 comments:

Anonymous said...

Well, What is the OTHER product?

As stated the USB Anywhere 5 port hub wont cut the mustard and at $350 a box...

Anonymous said...

the other product is W&T 2-port dongle server (www dot wut dot de) and there is a third, a budget one on Amazon called LCS-US204 USB

Anonymous said...

and not to mention the cheap USB Anyshwere works only for ONE VM, the Multiport works for up to 5 different VM.

Anonymous said...

There are 2 more in the <75$ league:

Sharkoon USB Lanport 400
Longshine LCS-US204

Both of them have a "client" mode which seems to be pretty reliable and a "server mode" which can't do anything reasonable like doing the fileserver thing on an externa USB HD (if it's NTFS and/or > 2TB)

Common for all of the cheaper devices is the fact that the drivers are only for Win7, if the driver is installable on Win2008R2 you might feel lucky :-)