From: Bit Gossip (bit.gossip@chello.nl)
Date: Sat Aug 18 2007 - 07:07:14 ART
Lim,
by default
The formula for metric is: m=2.56*10^12/bw + 256 * (D/10)
Bit.
----- Original Message -----
From: "Toh Soon, Lim" <tohsoon28@gmail.com>
To: "Bit Gossip" <bit.gossip@chello.nl>
Cc: "Sadiq Yakasai" <sadiqtanko@gmail.com>; <ccielab@groupstudy.com>
Sent: Friday, August 17, 2007 3:50 PM
Subject: Re: How offset-list works in EIGRP?
> Hi Bit,
>
> Good job there!
>
> Now we know the offset is added to the composite metric. Whether it's
> applied outbound/inbound, the router will adjust the total delay component
> to produce that offseted composite metric.
>
> Hey, where did you find that wonderful formula?
>
> 10 microsend of delay = 256 metric unit
>
>
> Thank you.
>
> B.Rgds,
> Lim TS
>
>
>
> On 8/17/07, Bit Gossip <bit.gossip@chello.nl> wrote:
>>
>> Ok, now I think I understand the trick: the lab proved that 1 offset
>> unit
>> = 1 metric unit
>> Then IOS, to keep the metric consistent with the variables that determine
>> the metrics, adjusts the delay accordingy:
>>
>> 10 microsend of delay = 256 metric unit
>>
>> And this is exactly what we can see in the lab:
>>
>> R6(config)#router eigrp 1
>> R6(config-router)#offset-list 0 in 256
>> R6(config-router)#
>> *Mar 1 22:56:44.343: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor
>> 1.1.1.1(Serial0/1) is resync: route configuration changed
>> R6(config-router)#do show ip eigrp 1 topology 150.1.1.0/24
>> <....>
>> Total delay is 25010 microseconds
>> R6(config-router)#offset-list 0 in 128
>> *Mar 1 22:58:21.426: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor
>> 1.1.1.1(Serial0/1) is resync: route configuration changed
>>
>> do show ip eigrp 1 topology 150.1.1.0/24
>> <....>
>> Total delay is 25005 microseconds
>>
>> And without any offset-list the total delay is 25000 !
>>
>> Two bits from bit.
>>
>> ----- Original Message -----
>>
>> *From:* Toh Soon, Lim <tohsoon28@gmail.com>
>> *To:* Bit Gossip <bit.gossip@chello.nl>
>> *Cc:* Sadiq Yakasai <sadiqtanko@gmail.com> ; ccielab@groupstudy.com
>> *Sent:* Thursday, August 16, 2007 10:30 AM
>> *Subject:* Re: How offset-list works in EIGRP?
>>
>>
>> Hi Bit,
>>
>> If you do "sh ip ei top 150.1.1.0 255.255.255.0", do you notice there's
>> an
>> increase in the total delay component of the route?
>>
>> This delay value will be propagated to downstream neighbors, effectively
>> causing all downstream routers to offset the metric of the route by 1.
>> Correct me if I miss any point.
>>
>>
>> Thank you.
>>
>> B.Rgds,
>> Lim TS
>>
>>
>> On 8/16/07, Bit Gossip <bit.gossip@chello.nl> wrote:
>> >
>> > Here the docs seems not to be correct: an offset of 1 adds just 1 to
>> > the
>> > metric not 256 as someone would understand from doccd
>> >
>> > Bit.
>> >
>> > no offset-list applied:
>> >
>> > R6#show ip route
>> > <....>
>> > D 150.1.1.0 [90/20640000] via 1.1.1.1, 00:00:13, Serial0/1
>> >
>> > ~~~~~~~~~~~~~~~~~~~~~
>> >
>> > router eigrp 1
>> > offset-list 0 in 1
>> >
>> > R6(config-router)#do show ip route eigrp 1
>> > 150.1.0.0/24 is subnetted, 1 subnets
>> > D 150.1.1.0 [90/20640001] via 1.1.1.1, 00:00:06, Serial0/1
>> >
>> > ----- Original Message -----
>> > From: "Sadiq Yakasai" <sadiqtanko@gmail.com>
>> > To: "Toh Soon, Lim" <tohsoon28@gmail.com>
>> > Cc: <ccielab@groupstudy.com>
>> > Sent: Wednesday, August 15, 2007 6:48 PM
>> > Subject: Re: How offset-list works in EIGRP?
>> >
>> >
>> > > Hi Toh,
>> > >
>> > > EIGRP offset list add the delay components on the composite metric
>> > > addvertised either in or out of an interface.
>> > >
>> > > For example, if u configure an offset-list and add 1 to an inbound
>> > > interface, all EIGRP routes learnt via that interface will increment
>> > > the delay component of the route by 1, thereby incresing the total
>> > > metric by 256.
>> > >
>> > > HTH
>> > >
>> > > Sadiq
>> > >
>> > >
>> > _______________________________________________________________________
>> > > Subscription information may be found at:
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>
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