CB-GTS with CB-WFQ using NBAR

Hey all,

Every time i think I have a grasp on QoS I hit more issues.

Firstly here is what I think I know (don't worry, its not much.. random numbers used, typos excused)

1) When you setup just QoS using the MQC you can match protocols under class-maps via NBAR example:

!
class-map CMAP_ICMP
 match proto icmp
!
policy-map PMAP_ICMP
 class CMAP_ICMP
  priority 54 4000
!

2) When you shape you use the CB-GTS to shaping as follows:
!
policy-map PMAP_SHAPE
 class class-default
  shape ave 51200 8000 0
!



Ok, so what gives here & my question(s) arise.

1) If i want to then use my CBWFQ policy that uses NBAR matching I cannot nest this inside a CB-GTS like so;

!
policy-map PMAP_SHAPE
 shape ave 51200 8000 0
 service-policy PMAP_ICMP
!

*note i was applying this to a sub-interface fe0/0.1 if that is why I had problems.



2) To make this work, I need to change my CBWFQ policy so that it does not use NBAR matching as follows:

!
ip access-list ext ACL_ICMP
 permit icmp any any
!
class-map CMAP_ICMP
 match access-gro ACL_ICMP
!

*And this now will nest happily under the CB-GTS.



So, and thanks for sticking with me, what I want to know is, is this statement true:

When performing CB-GTS (regardless of interface) you cannot nest a CB-WFQ policy that uses NBAR matching.....


I have done my googling, but you know I find it easier to write this out, helps me visualize the problem.

If you can put me right, I would be most grateful.. :)


Your pal,

\Sam