QOS query - Bandwidth remaining percent

[vvvvvbbb123]

Hi Team,

I am confused with the "bandwidth remaining percent" concept of cisco.

consider the bandwidth of 300 M and below is the queing policy configured.

policy-map Queue

 class class-default

  shape average 300000000

  service-policy OUT

policy-map OUT

 class EF

  priority 4096

 class MGMT

  bandwidth remaining percent 1 

 class BUSINESS

  bandwidth remaining percent 97 

  shape average 290000000

  service-policy APP

 class default-out

  bandwidth remaining percent 1 

  shape average  150000000

policy-map APP

 class AF4X

  bandwidth remaining percent 9

  queue-limit 8694 packets

 class AF3X

  bandwidth remaining percent 14

  queue-limit 11184 packets

 class AF2X

  bandwidth remaining percent 3

  queue-limit 4098 packets

 class Rest

  bandwidth remaining percent 71

  random-detect dscp-based

  random-detect exponential-weighting-constant 10

  random-detect dscp 10 12500 37500 1

  random-detect dscp 12 7500 25000 1

  queue-limit 37500 packets

Now my question is what would be the actual value for Class AF4X would it be 

A > 25832 (this value is arrived by 300000 -Priority value and considering this to be 100% value for remaining BW calulation) or 

B> 26631 (this value is arrived by 300000 - Priority = resultant value 97% and this value is considered to be 100% for subclass ie BUSINESS_C calculation).

Bare my English mistakes

Regards,

VB

[Joseph W. Doherty]

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Posting

(Have you been able to apply this config to an interface?)

I think what should happen is class AF4X should obtain a minimum of 9% of 290000000 (because I believe it uses the parent's class shaper as its reference bandwidth - oh, and 9% because all your APP classes use bandwidth remaining [they also didn't allocate 100%, so the AF4X class should get even more than 9% even if all other classes want more than their minimums]).

[vvvvvbbb123]

Yes, this is a working configuration. As i was told to provide the values in Kb, i was bit confused.

[Joseph W. Doherty]

Disclaimer

The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.

Liability Disclaimer

In no event shall Author be liable for any damages wha2tsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.

Posting

Provide bandwidth it Kb?  Hmm, just a different (and original) way of providing bandwidth settings for classes.  I.e. how the policy will behave, doesn't change, but makes it more difficult to maintain the policy across multiple interfaces.

[vvvvvbbb123]

yes Joseph... i understand it is difficualt, but my client wants that way.. So i am assigned to change from percentage actual values....

Also do you have any document which says that shaper value will be taken as reference for calculating sub policy map values ?

[Joseph W. Doherty]

It might be in one of the following.

http://www.cisco.com/c/en/us/support/docs/routers/7200-series-routers/110850-queue-limit-output-drops-ios.html

http://www.cisco.com/c/en/us/td/docs/ios/qos/configuration/guide/15_1/qos_15_1_book/qos_frhqf_support.html

http://www.cisco.com/c/en/us/td/docs/ios/12_0s/feature/guide/12spctsg.html