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New Member

LLQ on GSR 12000 (priority and police commands)

Hello,

I am currently trying to deploy QoS in a network's core built with 12000 GSRs. I need to give strict priority to a voice class traffic (LLQ), but I have found that here the command "priority" can not use a bandwidht or percentage value. Instead, I believe that it is necessary to configure also a "police" command to limit the amount of traffic to be prioritized.

My question is... how should I configure that police in order to achieve the same results the command "priority <bandwidth>" has in all other platforms?

"same results" means that the defined amount of traffic gets priority and the rest is queued but not dropped.

Thanks for your help.

3 REPLIES
Silver

Re: LLQ on GSR 12000 (priority and police commands)

Hey,

You're right, the GSR, and certain other modules for higher platforms only supports a 'strict priority' queue, without any built-in policer.

By default, the built-in policer has a CIR of the value you specify after the 'police' statment, with a BC of 1/40 of that. It also gives you the option of changing the BC, with a 3rd optional parameter.

If you want to create the same behavior in your CIR, put in a police statement with the desired CIR, and a burst of 1/40.

For instance, if you want to cap it off at 320kbps,

configure this:

policy-map voicepolicy

class voice

priority

police 320000 8000 0 conform-action transmit exceed-action drop

Will

New Member

Re: LLQ on GSR 12000 (priority and police commands)

Thanks Will,

It seems to be that's the way to limit the priority traffic.

I believe that my other option is to configure only the priority command under that class, although, in that way the voice traffic is not going to have any limit, therefore, all the other classes will suffer in case of congestion.

Re: LLQ on GSR 12000 (priority and police commands)

That's correct.

The reason why the GSR doesn't support granular LLQ is because it mostly functions at the core and the core devices should be able to switch packets fast with minimal processing. I would assume you have high speed link/circuits and resources like bandwidth/CPU mayn't be a constraint. With the built-in capacity of GSR voice mayn't suffer any delay.

HTH,

Sundar

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