Re: BGP advertise non best routes?

Hey Marc-
What you may be looking for is multipath, using the maxium-path
statement.
 
http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a0080094431.
shtml

Regards,
Jay McMickle- CCIE #35355
 

From: marc abel
<marcabel_at_gmail.com>
To: john matijevic <john.matijevic_at_gmail.com>
Cc: Group
Study <ccielab_at_groupstudy.com>
Sent: Sunday, May 13, 2012 2:07 PM
Subject:
Re: BGP advertise non best routes?

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.
> >
> >
> > Blogs and organic groups at http://www.ccie.net
> >
> >
Received on Sun May 13 2012 - 14:03:34 ART