frame-relay class vs. interface-dlci class

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Aug 22nd, 2007
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What is the difference between assigning your QoS policy map using the frame-relay class <class name> on the subinterface and assigning the QoS policy map under the interface-dlci statement?

Correct Answer by Edison Ortiz about 9 years 9 months ago

The frame-relay class will apply the QoS on all PVCs in that interface while the QoS under the interface-dlci statement will only apply the QoS for that PVC.


For instance, you have 3 PVCs pointing to one serial interface (101, 201 and 301) and only want to assign a CIR of 128kbps to DLCI 201. If you apply a frame-relay class under the serial interface, all PVCs will inherit the 128kbps CIR. If you only want DLCI 201, you must apply it under the interface-dlci.


HTH,



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Correct Answer
Edison Ortiz Wed, 08/22/2007 - 14:20
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The frame-relay class will apply the QoS on all PVCs in that interface while the QoS under the interface-dlci statement will only apply the QoS for that PVC.


For instance, you have 3 PVCs pointing to one serial interface (101, 201 and 301) and only want to assign a CIR of 128kbps to DLCI 201. If you apply a frame-relay class under the serial interface, all PVCs will inherit the 128kbps CIR. If you only want DLCI 201, you must apply it under the interface-dlci.


HTH,



mlitka Thu, 08/23/2007 - 05:10
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Ahhh OK. That makes perfect sense. What about if this policy is doing shaping? Do I have to apply 'frame-relay traffic shaping' to the main interface? It is not on there now and appears to be working fine.

Edison Ortiz Thu, 08/23/2007 - 05:56
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The frame-relay traffic shaping command isn't allowed under the frame interface-dlci section.


You only have one option, apply under the main serial interface.


If you have other DLCIs under that main interface, they will automatically default their CIR to 56kbps so be sure to create a global frame-map/QoS for the remaining DLCIs if they aren't running at 56kbps.


If you have sub-interfaces, the process is a lot simpler. You would create the shaping and class directly onto the sub-interface without affecting other DLCIs.

mlitka Thu, 08/23/2007 - 06:23
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We use sub-interfaces. I can apply the frame-relay class statement under the sub-interface. The question is, since this statement is doing shaping to the default class and then has another nested policy under it, would I still need to apply 'frame-relay traffic shaping' under the main interface? It seems to be working fine without it.


Please advise.

Edison Ortiz Thu, 08/23/2007 - 08:32
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Are you doing Generic Traffic Shaping (GTS) or Frame-Relay Traffic Shaping (FRTS) ?


If you are doing FRTS, you need the frame-relay traffic shaping in order to shape the traffic.


Can I see the portion of the config we are dealing with ?


Can I also see the output from typing


show frame traffic-shaping

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