From: Petr Lapukhov (petrsoft@gmail.com)
Date: Sun Mar 05 2006 - 13:05:58 GMT-3
Hello Sameer,
AFAIK both of concepts are not that different: the uderlying mechanics
is the _same_ exponential decay.
The only notably difference of Interface Dampening
is that it hides interface, (not the prefix in BGP table), from routing
proccess
(they see it as down).
Another difference I must note - IP event dampening uses
1-30 seconds values for HLife (quick suppression), while BGP uses
minute-resolution timers.
WBR
Petr
--2006/3/5, sameer azam <sameer.azam@gmail.com>: > > HI, > Guys i was talking about the DAMPENING on the INTERFACE > not in the BGP, which is different . > regards > > > On 3/5/06, Petr Lapukhov <petrsoft@gmail.com> wrote: > > > > Hi, > > > > hm, let's see :) > > > > If we got 1000 for every flap, then for 3 quick flaps in a row, > > theoretically, we accumulate 3000. If Suppress value is set to 2000 > > then after those three flaps we got our interface suppressed. Now > > penalty starts to decay exponentially by simple law > > > > CurrentPenalty = StartPenalty*2^(-t/HLife) (it halves every HLife time) > > > > Interface become unsuppressed when CurrentPenalty hits ReuseValue. > > > > Now, half of 3000 is 1500, and thus, by setting Half-Life to 30 secs, > > and Reuse Value > > to 1500, we could get close to desired result. > > > > dampening 30 1500 2000 100 > > > > Why MaxSuppressTime is 100? Well maximum _possible_ PenaltyValue is > > 20000. > > and our > > > > > > MaxPenalty = ReuseV*2^(MaxST/HLife) - this is the penalty value, > > which decays to ReuseValue in MaxSuppressTime. > > > > So setting MaxST to 100, brings MaxPenalty below the possible limit, but > > > > setting it to 120, makes MaxPenalty jump over. > > > > > > HTH > > Petr > > > > --- > > > > > > 2006/3/5, sameer.azam@gmail.com < sameer.azam@gmail.com>: > > > > > Hi, > > > > > > Is there is a Way to calculate the value of DAMPENING command, such as > > > > > > Half Life > > > Reuse Limit > > > suppress-threshold > > > max-suppress-time > > > > > > Ok Wt i know from the command reference is that > > > > > > Max-suppress-time = 4 x Half Life > > > > > > But how to answer the following Question: > > > > > > Dampen the route when the link flaps 3 times then suppress the > > > route for 30 Sec. > > > > > > Regards > > > > > > _______________________________________________________________________ > > > > > > Subscription information may be found at: > > > http://www.groupstudy.com/list/CCIELab.html
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