Re: Filtering Routes in RIP

Only gateways permitted by the prefix-list (Gateway_R4) will be will be
allowed to proceed to be filtered by the prefix-list (ALLOW_SPECIFIC). In
your case 155.1.0.4/32 will be denied and therefore like Yuri mentioned -
30.0.0.0/14 will be permitted except from a source of 155.1.0.4/32.

-SL
**

On Mon, Aug 22, 2011 at 10:24 AM, Marko Milivojevic <markom_at_ipexpert.com>wrote:

> Have you labbed this up?
>
> I just opened my eyes, but I'm pretty certain it's a logical AND not OR.
>
> --
> 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
> Community: http://www.ipexpert.com/communities
>
> :: Sent from my phone. Apologies for errors and brevity. ::
>
>
> On Aug 22, 2011, at 4:26, sameer khan <khanzadap_at_hotmail.com> wrote:
>
> > No i don't mean logical AND. i ment it what i ment it, a logical OR. That
> is what is happening in reality. I know it is poorly documented and there
> is confusion about it.
> >
> >
> > the command below will ALLOW 30.0.0.0/14 from any ROUTE-SOURCE OR
> It will DENY all routes from ROUTE-SOURCE 155.1.0.4 but allow all other. it
> doesn't mean that deny 30.0.0.0/14 from ROUTE-SOURCE 155.1.0.4. just lab
> it up :)
> >
> >
> > distribute-list prefix ALLOW_SPECIFIC gateway GATEWAY_R4 in Serial0/0
> >
> >
> >
> >
> > I hope that it will clear things up a bit.
> >
> >
> >
> >
> > ----------------------------------------
> >> Date: Sun, 21 Aug 2011 23:47:34 -0700
> >> Subject: Re: Filtering Routes in RIP
> >> From: yuribank_at_gmail.com
> >> To: khanzadap_at_hotmail.com
> >> CC: roy.waterman_at_gmail.com; bxperts_at_gmail.com; ccielab_at_groupstudy.com
> >>
> >> Actually, I think you mean to say it is a logical AND operation.
> >>
> >> Both conditions must be met. The actual route must match against
> >> <routeprefixlist>, and the route source must match against
> >> <gatewayprefixlist>.
> >>
> >> So in the OP configuration:
> >>
> >> ip prefix-list ALLOW_SPECIFIC
> >> seq 5 permit 30.0.0.0/14
> >> seq 10 deny 0.0.0.0/0 le 32
> >>
> >> ip prefix-list GATEWAY_R4
> >> seq 5 deny 155.1.0.4/32
> >> seq 10 permit 0.0.0.0/0 le 32
> >>
> >> router rip
> >> version 2
> >> distribute-list prefix ALLOW_SPECIFIC gateway GATEWAY_R4 in Serial0/0
> >>
> >>
> >> This will match: ONLY 30.0.0.0/14 from any source EXCEPT 155.1.0.4/32,
> for
> >> Serial0/0
> >>
> >>
> >> -Yuri
> >>
> >> On Sun, Aug 21, 2011 at 5:54 PM, sameer khan <khanzadap_at_hotmail.com>
> wrote:
> >>
> >>> That to the best of my understand is incorrect. it will filter out all
> >>> routes from gateway 155.1.0.4 OR it will only permit 30.0.0.0/14 from
> any
> >>> other gateway. As i said before it is Logical OR operation and not
> logical
> >>> AND between the two prefix-list used.
> >>>
> >>> HTH
> >>>
> >>>
> >>>
> >>>> From: roy.waterman_at_gmail.com
> >>>> Date: Sun, 21 Aug 2011 23:15:44 +0100
> >>>> Subject: Re: Filtering Routes in RIP
> >>>> To: bxperts_at_gmail.com
> >>>> CC: ccielab_at_groupstudy.com
> >>>>
> >>>> Hi Shahid
> >>>>
> >>>> In the case of your config, only the prefix 30.0.0.0/14 will be
> accepted
> >>>> from all gateways apart from 155.1.0.4, for updates received on
> >>> serial0/0.
> >>>>
> >>>> Regards
> >>>> Roy
> >>>>
> >>>> On 20 August 2011 22:01, Shahid Mushtaq <bxperts_at_gmail.com> wrote:
> >>>>
> >>>>> Dears,
> >>>>>
> >>>>>
> >>>>>
> >>>>> I want to filter specific routes in RIP from one gateway while
> allowing
> >>>>> from
> >>>>> others.
> >>>>>
> >>>>>
> >>>>>
> >>>>> If I have the following configuration then how the routes will be
> >>> treated.
> >>>>> The distribute-list will only allow "30.0.0.0/14" from all gateways
> or
> >>> it
> >>>>> will be only specific to "155.1.0.4" gateway.
> >>>>>
> >>>>>
> >>>>>
> >>>>> To more specific, the distribute will go to check the check the
> prefix
> >>> then
> >>>>> the gateway or some other method.
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>> ip prefix-list ALLOW_SPECIFIC
> >>>>>
> >>>>> seq 5 permit 30.0.0.0/14
> >>>>>
> >>>>> seq 10 deny 0.0.0.0/0 le 32
> >>>>>
> >>>>>
> >>>>>
> >>>>> Ip prefix-list GATEWAY_R4
> >>>>>
> >>>>> seq 5 deny 155.1.0.4/32
> >>>>>
> >>>>> seq 10 permit 0.0.0.0/0 le 32
> >>>>>
> >>>>>
> >>>>>
> >>>>> Router RIP
> >>>>>
> >>>>> Version 2
> >>>>>
> >>>>> distribute-list prefix ALLOW_SPECIFIC gateway GATEWAY_R4 in Serial0/0
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>> Regards,
> >>>>>
> >>>>>
> >>>>>
> >>>>> Shahid
> >>>>>
> >>>>>
> >>>>> Blogs and organic groups at http://www.ccie.net
> >>>>>
> >>>>>
> _______________________________________________________________________
> >>>>> Subscription information may be found at:
> >>>>> http://www.groupstudy.com/list/CCIELab.html
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>
> >>>>
> >>>> --
> >>>> Regards
> >>>> Roy
> >>>>
> >>>>
> >>>> Blogs and organic groups at http://www.ccie.net
> >>>>
> >>>>
> _______________________________________________________________________
> >>>> Subscription information may be found at:
> >>>> http://www.groupstudy.com/list/CCIELab.html
> >>>
> >>>
> >>> Blogs and organic groups at http://www.ccie.net
> >>>
> >>> _______________________________________________________________________
> >>> Subscription information may be found at:
> >>> http://www.groupstudy.com/list/CCIELab.html
> >>
> >>
> >> Blogs and organic groups at http://www.ccie.net
> >>
> >> _______________________________________________________________________
> >> Subscription information may be found at:
> >> http://www.groupstudy.com/list/CCIELab.html
> >
> >
> > Blogs and organic groups at http://www.ccie.net
> >
> > _______________________________________________________________________
> > Subscription information may be found at:
> > http://www.groupstudy.com/list/CCIELab.html
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html

Blogs and organic groups at http://www.ccie.net
Received on Mon Aug 22 2011 - 10:31:31 ART