Perhaps my understanding is not great, but I can't get the QoS to work for my situation on a 2820 using firmware 3.3.3_232201. Can anyone help?

I have a terminal server. It's NATted through port 3399 on the external side to 3389 on the terminal server. I have another server performing mail duties. There are about 25 clients internally.

The remote workers using the terminal server suffer under a couple of situations.

If a number of people are downloading so that the download is saturated, the remote workers suffer.

If the mail server is sending out a mailshot so the upload is saturated, the remote workers suffer.

If internal users are using other apps that use various ports saturating both directions, the remote workers suffer.

Therefore I decided to try the QoS. I've created two new services on ports 3389 and 3399. I've added these in to Class 1. HTTP/HTTPS are in Class 2 and SMTP in Class 3. I've left all the classes set to 25% whilst testing and enabled TCP ACK prioritise. I've tried specifying the local address in Class 1, and selecting Any.

All remote worker traffic gets classified as Others; the Class 1 never shows any throughput on the statistics bar chart.

However, if I connect from an internal machine to an external terminal server, RDP throughput shows on the statistics bar chart! This is the wrong way around for this exercise.

As outbound SMTP and inbound HTTP responses both affect the inbound RDP remote workers, I've selected the direction as BOTH, but I've tried all the options and none seem to work, remote worker traffic is always classified as Others.

Help! My terminal server users are giving me grief because of the lack of usability!