I have implemented 2 classes using CBWFQ, one is default class and other scavenger class (CS1). The CS1 class is being used to control a centralised email system from impacting on all other WAN applications. There are many different sized WAN links from 1.4Mbps upto 100Mbps. I have used CBWFQ to assign 20% to CS1 class and the remainder to default class. Everything tests ok, BUT under congestion, because I have had to remove 'fair-queuing' on default class (because I needed to apply 'bandwidth percent X'), obviously small packets are now affected.
Question is, is there anyway I can guarantee the 'default class' of remaining BW and still allow email to get 20%, but using fair queuing on Default Class?