When USB mass storage drives are re-directed to an ICA session from an endpoint using USB re-direction, randomly over a period of time, the performance of the USB drive goes down and eventually gets into a non-responsive state.

Citrix recommends Client Drive Mapping (CDM) technology to be leveraged for client drive re-direction as the primary solution. CDM is the technology that has been specifically designed to optimize traffic, when dealing with storage devices.

The CDM can be enabled by using the HDX policy named Client drive redirection in Citrix Desktop Studio.

For further reference on how to enable CDM, see Citrix Product Documentation - File Redirection policy settings.

Problem Cause

The USB protocol generates a high volume of packets during interactions, which leads to performance issues. There are thousands of messages sent back and forth between the OS and the device. Because of this, it is completely conceivable that over a network you could see problems when multiple devices are all trying to send this data back and forth in large volumes. This can cause a lot of delay in data transmission eventually affecting the performance of the USB redirected drive.

Under ideal circumstances, the USB re-direction works as expected. But when there is a network latency/disturbance in the environment, the performance of USB re-directed drives would be hampered while using USB re-direction methodology and eventually not respond over a period of time.

CTX113480 - Error: Cannot copy (file name):Invalid MS-DOS Function... when using Client Drive Mapping and Files Larger than 2 GB

CTX134844 - Client Drive Mapping Failing for Files Larger than 4GB

CTX123569 - XenDesktop USB Citrix Tested Device List

USB re-direction methodology should only be used in fallback scenarios where the primary intended technology does not work or the device being used does not fit into another category.

Example