Re: BGP advertise non best routes?

Thank you, this idea has some potential.

On Sun, May 13, 2012 at 2:53 PM, Oluwagbenga Oyebande <
Oluwagbenga_at_daitmail.com> wrote:

> In the case of RIB failure "r>" BGP process will still consider the route
> as best path and advertise it to neighbor.
>
> So if you can induce a rib failure by lowering IGP AD on the router to
> prefer IGP route to BGP route. This should do the trick. RR will not use
> the BGP route, but will still see it as Best path and advertise it to
> neighbor.
>
>
> On 13 May 2012 20:07, marc abel <marcabel_at_gmail.com> wrote:
>
>> Thank you for your response john. I may not have explained what I am
>> trying
>> to do well enough.
>>
>>
>> what I am talking about is if you have two paths in the bgp table such as
>> this:
>>
>> R3(config-if)#do show ip bgp
>> BGP table version is 21, local router ID is 1.1.3.3
>> Status codes: s suppressed, d damped, h history, * valid, > best, i -
>> internal,
>> r RIB-failure, S Stale
>> Origin codes: i - IGP, e - EGP, ? - incomplete
>>
>> Network Next Hop Metric LocPrf Weight Path
>> * i100.100.1.0 10.1.2.254 0 100 0 500 i
>> *>i 10.1.1.254 0 100 0 500 200 i
>>
>> Your router will only advertise out the route it considers best to its BGP
>> peer. So in this case it would only advertise the route through
>> 10.1.1.254.
>> What I want is to be able to send both options to the next router in the
>> line and then let it choose based on weight or as path or something.
>>
>> *note I have applied "bgp bestpath as-path ignore" that is why this one
>> isn't preferring the shorter AS path.
>>
>>
>>
>>
>> On Sun, May 13, 2012 at 1:49 PM, john matijevic <john.matijevic_at_gmail.com
>> >wrote:
>>
>> > Good Afternoon Marc,
>> >
>> > "Is there any way to force BGP to advertise all of it's routes, even
>> ones
>> > it
>> > doesn't consider best? "
>> >
>> > You can use the network statement under the BGP process to advertise
>> > the connected networks. For routes learned via another protocol, you
>> > can use the redistribute command.
>> >
>> > Once you have all the routes that you want advertised you can use
>> > different filter techniques to advertise or bgp attributes command to
>> > prefer one path over another.
>> >
>> > Hope this helps.
>> >
>> > Regards,
>> > John
>> >
>> >
>> > On 5/13/12, marc abel <marcabel_at_gmail.com> wrote:
>> > > Is there any way to force BGP to advertise all of it's routes, even
>> ones
>> > it
>> > > doesn't consider best? Particularly looking for a way to make an iBGP
>> > peer
>> > > prefer a different route than it's route reflector.
>> > >
>> > >
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>> > >
>> > >
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>>
>>
>>
>>
>
>
> --
> Olugbenga Oyebande
> MD, DAIT
> 234-803-302-5287
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> Cisco Networks, Network Security & Quality of Service
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Received on Sun May 13 2012 - 15:16:08 ART