Showing results for 
Search instead for 
Did you mean: 

Qos Shaping

Khurram Noor

Hi there,


I have a question regarding the below config:


class-map match-any cm-prec-1-out

match ip precedence 1

class-map match-any cm-prec-0-out

match ip precedence 0

class-map match-any cm-prec-3-out

match ip precedence 3

class-map match-any cm-prec-2-out

match ip precedence 2

class-map match-any cm-prec-5-out

match ip precedence 5

class-map match-any cm-prec-4-out

match ip precedence 4


policy-map pm-queue

class cm-prec-5-out

  priority percent 30

class cm-prec-4-out

  bandwidth remaining percent 15

 class cm-prec-3-out

  bandwidth remaining percent 30

 class cm-prec-2-out

  bandwidth remaining percent 15

 class cm-prec-1-out

  bandwidth remaining percent 10

 class cm-prec-0-out

  bandwidth remaining percent 5

 class class-default


policy-map pm-shape-queue-out

description *** Shape and Queue ***

class class-default

  shape average 3000000000

  service-policy pm-queue


The QoS policy is applied to he  WAN facing interface:

interface TenGigabitEthernet0/1/0

bandwidth 3000000

ip address x.x.x.x

ip nat outside

ip flow ingress

service-policy output pm-shape-queue-out


this policy is applied to a ten gig interface to limit the traffic to 3 gig. The customer is not actually marking anything except PREC 5, but this is a standard qos policy by SP. The policy allows 3 gig until windows update server starts sending data on the link. After it starts the link doesnt allow more than 2.2 Gig traffic flow. The ping latency on the link increases from 10ms to 116ms. Can someone assist what looks wrong with this policy?

1 Reply 1

vivek srivastava
Rising star
Rising star

1) can you share the output of "show policy-map interface TenGigabitEthernet0/1/0"

2) Have you checked the HW limitations (if any), i.e. forwarding rate supported in a perticular plateform and slot/card. Mostly seen in 7600.

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community:

Recognize Your Peers