Re: RPF Query!!!!!!!!!!

You are welcome :-).

--
Marko Milivojevic - CCIE #18427
Senior Technical Instructor - IPexpert
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On Thu, Nov 18, 2010 at 14:49, CCIE KID <eliteccie_at_gmail.com> wrote:
> Ok marko got ur point buddy
> thanks for the help
> now understood completely after reading RFC for RPF in multicasting
>
> Thanks Marko
>
> On Thu, Nov 18, 2010 at 8:09 PM, CCIE KID <eliteccie_at_gmail.com> wrote:
>>
>> It will take both the paths or else which path the multicast packet wll
>> take to reach the source
>> it cant take two paths
>> which path it will take
>>
>>
>> On Thu, Nov 18, 2010 at 8:05 PM, Marko Milivojevic <markom_at_ipexpert.com>
>> wrote:
>>>
>>> It would be reflected back to R1.
>>>
>>> --
>>> Marko Milivojevic - CCIE #18427
>>> Senior Technical Instructor - IPexpert
>>>
>>> FREE CCIE training: http://bit.ly/vLecture
>>>
>>> Mailto: markom_at_ipexpert.com
>>> Telephone: +1.810.326.1444
>>> Web: http://www.ipexpert.com/
>>>
>>> On Thu, Nov 18, 2010 at 14:33, CCIE KID <eliteccie_at_gmail.com> wrote:
>>> > ok marko i understood ur point
>>> > So in ur scenario in the full mesh topology the loop happens
>>> > wat about this scenario
>>> >
>>> > B B B B  s0/1
>>> > R1--------------------R2----------------------R3-
>>> > B |B  fa0/1 B B B B B B B B B B B B B B B B B B B B  |
>>> > B |B B B B B B B B B B B B B B B B B B B B B B B  |
>>> > B |B B B B B B B B B B B B B B B B B B B B B B B  |
>>> > B |-------------------------|
>>> >
>>> >
>>> > In this scenario if in IGP there are two routes which R2 can reach R1
>>> > thorugh serial and fastetherent
>>> > In this case wat would be the multicast path
>>> > which path it would take if the packet comes from two paths
>>> >
>>> >
>>> > On Thu, Nov 18, 2010 at 7:54 PM, Marko Milivojevic
>>> > <markom_at_ipexpert.com>
>>> > wrote:
>>> >>
>>> >> There is no RPF in that scenario and that's what would happen.
>>> >> However, with RPF, when each of the routers receives copy of the
>>> >> traffic from non-RPF interface, it will drop it.
>>> >>
>>> >> --
>>> >> Marko Milivojevic - CCIE #18427
>>> >> Senior Technical Instructor - IPexpert
>>> >>
>>> >> FREE CCIE training: http://bit.ly/vLecture
>>> >>
>>> >> Mailto: markom_at_ipexpert.com
>>> >> Telephone: +1.810.326.1444
>>> >> Web: http://www.ipexpert.com/
>>> >>
>>> >> On Thu, Nov 18, 2010 at 14:21, CCIE KID <eliteccie_at_gmail.com> wrote:
>>> >> > No marko can u be little more clear
>>> >> > wat is ur scenario deals wid RPF
>>> >> >
>>> >> >
>>> >> > On Thu, Nov 18, 2010 at 7:47 PM, Marko Milivojevic
>>> >> > <markom_at_ipexpert.com>
>>> >> > wrote:
>>> >> >>
>>> >> >> A---B
>>> >> >> | X |
>>> >> >> C---D
>>> >> >>
>>> >> >> So, we have full mesh of connections between A, B, C and D. Source
>>> >> >> is
>>> >> >> attached to A. Source sends packet, A replicates it to B, C and D.
>>> >> >> C
>>> >> >> replicates the packet to B and D (B and D receive their 2nd copy of
>>> >> >> the same traffic). When B receives this traffic for C it replicates
>>> >> >> it
>>> >> >> to D (3rd copy), and back to A. A replicates it back to C, D... etc
>>> >> >> etc etc. You get the idea?
>>> >> >>
>>> >> >> --
>>> >> >> Marko Milivojevic - CCIE #18427
>>> >> >> Senior Technical Instructor - IPexpert
>>> >> >>
>>> >> >> FREE CCIE training: http://bit.ly/vLecture
>>> >> >>
>>> >> >> Mailto: markom_at_ipexpert.com
>>> >> >> Telephone: +1.810.326.1444
>>> >> >> Web: http://www.ipexpert.com/
>>> >> >>
>>> >> >> On Thu, Nov 18, 2010 at 14:10, CCIE KID <eliteccie_at_gmail.com>
>>> >> >> wrote:
>>> >> >> > Hey i know the RPF check happens every time when a multicast
>>> >> >> > packet
>>> >> >> > comes to
>>> >> >> > router to check whether the same interface can be used to reach
>>> >> >> > the
>>> >> >> > source
>>> >> >> > of the multicast feed.Why does this has been done?? To avoid
>>> >> >> > loops!!!!
>>> >> >> > *WHy
>>> >> >> > RPF check is mandatory for a multicast packet*?
>>> >> >> > If to avoid loops Can u give me a classic case of loop formation
>>> >> >> > in
>>> >> >> > multicasting when RPF is not present
>>> >> >> >
>>> >> >> >
>>> >> >> > --
>>> >> >> > With Warmest Regards,
>>> >> >> >
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>>> >> > --
>>> >> > With Warmest Regards,
>>> >> >
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>>> >
>>> >
>>> >
>>> > --
>>> > With Warmest Regards,
>>> >
>>> > CCIE KID
>>> > IN PURSUIT OF CCIE
>>> >
>>
>>
>>
>> --
>> With Warmest Regards,
>>
>> CCIE KID
>> IN PURSUIT OF CCIE
>
>
>
> --
> With Warmest Regards,
>
> CCIE KID
> IN PURSUIT OF CCIE
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