Posted: Sun May 01, 2011 11:21 Post subject: hidden limitation in QoS class rules
The QoS class rules for the special edition are applied with both "rate" and "ceil" taking the values entered on the QoS page - the result is that totalling up the "rate" values can easily exceed your WAN limits - making the WAN limits and QoS ineffective - your link will saturate:-
The result of this rule is to guarantee each device 950Kbits/s, if your link is 1.5Mbits/s whilst one device would be limited to your requested value, two devices would be able to exceed your WAN limit and saturate your link.
The solution to this would be to set the "rate" values to something much lower which will reduce the chance of exceeding the WAN limits eg:-
Its hard to calculate a sensible number for the "rate" because the number of devices is unknown, but a preset value would be OK as it is only used for the guaranteed minimum bandwidth.