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Rate-limits Cisco Router

Hi all

I have a cisco router which uses rate-limits to control traffic inbound and outbound of each interface. The router is a 3600 and here is an example of one of the interfaces:

interface Serial2/2 bandwidth 2048 ip address 10.x.x.x 255.x.x.x ip verify unicast reverse-path no ip redirects no ip proxy-arp rate-limit input 1024000 25000 25000 conform-action transmit exceed-action drop rate-limit output 1024000 25000 25000 conform-action transmit exceed-action drop ip summary-address eigrp x 0.0.0.0 0.0.0.0 5 no ip mroute-cache ntp broadcast no cdp enable

Can someone please explain how the rate limits work?

Many thanks

Reply to
c1tc
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Hi, I wonder if this helps at all?

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Basically on your example here

rate-limit input 1024000 25000 25000 conform-action transmit exceed-action drop

this is a looking at data coming into the interface and limiting it to 1 megabit/s,

"conform-action transmit" means, "transmit anything that is below 1 megabit/s"

and this bit "exceed-action drop" means, "drop anything that is above 1 megabit/s"

The other two numbers are burst-normal - Normal burst size, in bytes. The minimum value is bps divided by 2000." burst-max which means - Excess burst size, in bytes

Though I must admit I don't really understand what those burst-normal and burst-max actually mean. Maybe someone else can explain.

Regards

Paul

Reply to
John Smith

Thanks Paul,

Can anyone else explain the difference between Normal and Excess burst rates and how they work?? I have read the Cisco literature but looking for an explanation in simple terms!

Also will the Bandwidth command have any effect on the traffic allowed through the interface?

cheers

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Reply to
c1tc

No. But it does affect metrics under OSPF which might make the route more or less desirable.

Reply to
John Smith

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