Re: Ignoring MED (BGP question)

There are four other attributes that are taken into account before MED:

1. Weight
2. Local preference
3. AS path
4. Origin

MED is an extremely weak metric in BGP. if you want to override
behavior using MED, just change it.

--
Marko Milivojevic - CCIE #18427
Senior Technical Instructor - IPexpert
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On Mon, Nov 22, 2010 at 04:28, Jack Router <pan.router_at_gmail.com> wrote:
> Perhaps I was not clear then...
>
> I am an ISP (AS12, R1, R2) and you are a client (AS34, R3, R4).
> I, the ISP do not like the idea that you (the client) tell me how to route
> packets on my network. I want to ignore MED you may send me from R3 or R4.
>
> B B B B  AS12
> R1----------R2
> |B B B B B B B B B B  |
> |B B B B B B B B B B  |
> R4----------R3
> B B B B  AS34
>
> This is not a real life example, I am only extending a lab from my workbook.
> In the lab I was asked to make sure that all traffic to AS34 uses link
> R2-R3. The solution is to set metric higher than 0 on R4 toward R1. I am now
> adding requirement to ignore this route manipulation and confgure
> accordingly routers in AS12.
>
>
> On 21 November 2010 22:21, Marko Milivojevic <markom_at_ipexpert.com> wrote:
>>
>> Just curious... What would be the reason to keep it if you are going
>> to ignore 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 Mon, Nov 22, 2010 at 03:16, Jack Router <pan.router_at_gmail.com> wrote:
>> > Thanks for your answer but it does not answer my question. The question
>> > was
>> > if it is possible to ignore a MED instead of setting metric=0.
>> >
>> > On 21 November 2010 20:29, Zack (Doc) <zack_at_tnan.net> wrote:
>> >
>> >> MED should only be compared (by default) when it's coming from the same
>> >> AS.
>> >> B Why do you want to ignore it? B Why is setting via RM not clean? B I
>> >> just
>> >> told my carrier to ignore my MED (cause they are using
>> >> "always-compare-med")
>> >> and I told them to put this on their existing RM
>> >>
>> >> route-map CUSTOMER_X_INBOUND permit 1
>> >> B set metric=0
>> >> B continue
>> >>
>> >> It's just that easy.
>> >>
>> >> On Sun, Nov 21, 2010 at 17:20, Jack Router <pan.router_at_gmail.com>
>> >> wrote:
>> >>
>> >> > Hello Experts,
>> >> > How to ignore MED information received from neigbouring EBGP router ?
>> >> > I
>> >> can
>> >> > set metric = 0 via a route-map but this is not as clean as ignoring
>> >> > an
>> >> > information would be
>> >
>> >
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>> >
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