[nsp] Distributed traffic shaping not working on 7500 with 12.2(6)?

From: Blaz Zupan (blaz@inlimbo.org)
Date: Thu Jan 03 2002 - 02:25:03 EST


I'm trying to use traffic shaping inside of CBWFQ on a 7507 running 12.2(6).
It doesn't seem to work at all. Here is what I have:

class-map match-all voip-customer
  match access-group 111
class-map match-all from-internet
  match ip dscp 38

policy-map voip-to-customer
  class voip-customer
    priority 512
policy-map to-customer
  class from-internet
    shape average 10240000 40960 40960
   service-policy voip-to-customer

interface FastEthernet6/1/0.8
  encapsulation dot1q 8
  service-policy output to-customer

So, I have a customer connected to a 802.1q VLAN on a FastEthernet interface.
I'm trying to limit his transit connectivity to 10Mbps and not limiting the
peering connectivity, while giving strict priority to his VoIP traffic (LLQ)
inside of the transit traffic.

The same configuration works wonderfully on a 7206VXR. But looking at "show
policy-map interface f6/1/0.8" on the 7507, I get:

 FastEthernet6/1/0.8

  Service-policy output: to-customer

    Class-map: from-internet (match-all)
      65373591 packets, 50749459632 bytes
      30 second offered rate 15929000 bps, drop rate 0 bps
      Match: ip dscp 38
      queue size 0, queue limit 251
      packets output 20701403, packet drops 0
      tail/random drops 128, no buffer drops 0, other drops 0
      Shape: cir 10240000, Bc 40960, Be 40960
        output bytes 15222747872, shape rate 3854000 bps
...
(cut for brevity)

As you can see, there is about 15Mbps of traffic going towards the customer,
but traffic shaping is only seeing it as 3.8Mbps of traffic, so it's not
dropping any of the packets (the drop rate is 0). It almost looks like shaping
is not seeing all of the packets. I have distributed CEF turned on (otherwise
I can't configure the service policy on the interface at all).

Making the shaping rate *very* low (like 1Mbps) does drop a couple of packets,
but still not enough (at a offered rate of 15Mbps with shaping rate set to
1Mbps, the drop rate is usually around 500K, which is still much more than the
10Mbps shaping CIR I want to achieve).

Any idea what is going on here? Why is this working on a 7206VXR, but not on
the 7507? This smells like another bug, although I'm pretty ignorant of the
75xx architecture and I might be misunderstading something. The 7507 has one
RSP2 and one VIP2-50.



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