Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

IP dampening


when a route flaps 3times in 30 sec period then suppressed from routng table.

how do i configure dampening about this?



Re: IP dampening

it is not at all possible to do it 30 secs as dampening works from minimum 1 min. best thing would be to leave it at default policies. This is sprint's implementation


VIP Purple

Re: IP dampening


if you are referring to IP Event Dampening, according to my calculations, the following values would apply:

dampening 30 3000 1000 120

A penalty of 1000 is applied each time the interface flaps, so you will need 3 flaps, or a penalty of 3000, for the interface to be dampened. The half-life is set to 30, which means that the penalty of 3000 can be accumulated during 30 seconds, after which the accumulated penalty decreases by half. The reuse-threshold (1000) and the max-suppress time (120 seconds) values are arbitrary, you might want to change those, if required.

Can you try and see if this works for you ?



New Member

Re: IP dampening

Hi folks

thanks for sincere responding..

GP, I thought just like your numbers in the first place, but it didn't work coz when second flap happen after 10sec later of first one, accumulated penalty goes to 1600 or something its not 2000 that means accumulated pernalty is decreasing every moment(mili second or somthing) its not like wait untill 30 seconds and cut to the hlaf... I think this is more complicated than what we think.

New Member

Re: IP dampening

On another conversation on netpro I saw that someone referenced to RIPE-229 they say that in there they show you how to "do the maths" but i saw the document and couldn't figure it out.... the most I did where some calculations in Excel, and what I saw is that if you use the command with just a 15 (dampening 15) then the interface would be dampened if it flapped at least 3 times during a 30 second period, but I'm not sure, so let me know if you find any usefull links on the web.



CreatePlease login to create content