Bandwidth on Ethernet

smallrain_2 · ‎04-04-2008

Hi,

I have a fast ethernet link to our ISP box. Our guranteed service is only 30Mbps.

What is the best way to configure our fast ethernet interface to limit traffic to 30Mbps?

Thanks,

Jon Marshall · ‎04-04-2008

You need to use shaping on your ethernet interface ie.

class-map match-all Class_Default

match any

!

policy-map WAN_Shape

class Class_Default

shape average 30000000

int fa0/1

service-policy output WAN_Shape

The ISP will probably police the traffic on their end but you are better off using shaping as it is a bit less drastic.

Jon

Joseph W. Doherty · ‎04-04-2008

Another option, your Ethernet interface might support GTS, e.g. "traffic-shape rate 30000000". However, I endorse Jon's suggestion of using CBWFQ for future QoS options.

PS:

BTW: class-default is an implict class, you shouldn't need to define a class-map for it.

Jon Marshall · ‎04-04-2008

"BTW: class-default is an implict class, you shouldn't need to define a class-map for it."

I know, i just thought it would be a better example rather than just a shape statement under the policy-map. Looking at it now you may have a point :-)

Jon

Joseph W. Doherty · ‎04-04-2008

It is a fine example, postscript was directed to other readers, such as perhaps OP, who might not have been aware of the fact.

smallrain_2 · ‎04-06-2008

Thanks all.