It appears that when QoS is turned off that all DSCP values are rewritten.
Example, I have four switches that are daisy changed to a router. The traffic is trusted on the receiving port but at the router I don't see any of the marked traffic. I'm assming that one of the trunk ports is rewritting the DSCP values.
Tthe following comand is returned on one of the interconnecting switches:
SHOW MLS QOS
QoS is disabled
QoS ip packet dscp rewrite is enabled
This leads to believe that the switch is rewritting the DSCP values because QoS is disable.