Hi David,
One thing has to be made clear. Citrix do not support USB redirection with XenApp server. Not for USB storage devices, nor USB Activesync nor USB printers. XenDesktop now supports USB redrection using the new HDX USB Virtual hub, XenApp doesn't.
Plugging in a USB storage device on a Windows system initiates the USBSTOR driver and mounts that USB device as a local drive. When you initiate an ICA or RDP session and have client drive remapping enabled, the client's local drives, including the USB storage device will be visible in the terminal services session.
But only when you start your terminal services session, not if the USB drive is plugged in later. DynamicUSB gets around this problem by dynamically linking USB storage drives to a subdirectory on the local user's C: drive. So all you're doing when you plug in a drive during a session is changing the contents of a directory. This is actually pretty elegant since it nicely gets around the need to restart a session to see a new local drive.
It turns out that USB redirection on a terminal server is both very easy and actually nearly impossible. Creating a redirected USB virtual hub isn't all that hard, but that's visible to every user on a terminal server. Session isolation and the incorporation of stuff like virtual loopbacks etc to support Activesync gets quite difficult.
To date the only company to support true isolated USB redirection on terminal services is Quest's provision Networks division (USB-IT). Trouble is USB-IT was only aimed at specified relatively low speed PDA devices and not a lot else (though it was extensible). We're working on something totally generic for USB-IT V2 but that's still a few months away before we've got something to show.
Otherwise there's always Server 2008/Windows 7 but from what I can tell I don't think that's going to be generic USB redirection either. But I could definitely be wrong.
It might be worthwhile to persevere with DynamicUSB. If it let you use a folder off a RAM disk on an embedded XP device it'd be perfect.
regards,
Rick
--
Ulrich Mack
Quest Software
Provision Networks Division
On Wed, Feb 11, 2009 at 8:16 AM, David Demers
<David.Demers@sos.state.co.us> wrote:
Sorry, specifically we are mostly dealing with USB portable drives.
What type of USB device are you attaching?
Hi guys,
I've been fighting with an issue with USB devices on my Windows XP Embedded devices. The problem is (as I'm sure many of you have experienced) that if a user plugs in a device after the ICA session has begun, the session does not detect the device being added. When we used Linux based thin clients this was not an issue, but it appears that the windows based ICA client is unable to provide this feature.
We found a nifty little utility called DynamicUSB (http://support.citrix.com/article/CTX112588) that sort of addresses this issue, but the basic premise and the assorted workarounds to make it palatable in our environment is frankly a bit cludgy. I was wondering if others are experiencing similar issues and/or what other methods have been employed to address this.
-David
P.S. Sorry if this is a double post… wasn't sure if the first one went to the correct address
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