Re: Poison-reverse

Hi Pramod,

Thanks for the detailed explanation.Is that mean,poison reverse is inbuild
on the routing protocol when it is configured and there wouldn't be
provision to enable or disable it ?.My basic curiousness for this question
arrived from seeing a "poison-reverse"command under ipv6rip.I am wondering,
is there a command related to poison-reverse on IPV4 distance vector routing
protocol.

Thanks

Regards
Anantha Subramanian Natarajan

On Mon, Aug 17, 2009 at 3:57 PM, Pramod G <learn02earn_at_gmail.com> wrote:

> Split horizon refers to the rule that information about a route will not be
> sent out the same
> interface or subinterface from which it was received (problem in multipoint
> configurations)
>
> no ip split-horizon for RIP networks
> no ip split-horizon as# for EIGRP networks
>
> Poison reverse The rule for poison reverse is to advertise a route out the
> interface on
> which it was received with an unreachable metric. Different routing
> protocols employ this
> rule at different times to control routing loops.
>
> The router sends a poison reverse update to remove a route and place
> it in holddown. This is done to avoid a routing loop
>
> On Mon, Aug 17, 2009 at 4:16 PM, Abraham, Tharak <tharakabraham_at_gmail.com
> > wrote:
>
>> Anantha,
>>
>> Distance vector protocols are/should be implemented with split horizon and
>> poison reverse !
>> Both are different concepts, but gives the best when it works together.
>>
>> Please refer to Jeff Doyle Vol 1, read through pages 89 and 90 (pdf) with
>> the examples.
>>
>>
>> Best Regards,
>> Tharak Abraham
>>
>>
>>
>> On Mon, Aug 17, 2009 at 9:27 PM, Anantha Subramanian Natarajan <
>> anantha.natarajan_at_gravitant.com> wrote:
>>
>> > Hi All,
>> >
>> > I have a question on poison-reverse,to activate or de-activate poison
>> > reverse for a distance vector routing protocols in cisco router,do we
>> have
>> > a
>> > specific command for the same.Otherwise it is enabled,when we enable
>> > split-horizon or it is enabled by default for all distance vector
>> routing
>> > protocol.I am sure missing something totally basic.Kindly help me to
>> > understand the same.
>> >
>> > Thanks
>> >
>> > Regards
>> > Anantha Subramanian Natarajan
>> >
>> >
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Received on Mon Aug 17 2009 - 16:07:34 ART