1)
On PE1
 vrf description customer
  rd 1:1
  route-target both 1:1
  route-target import 1:2
On PE2
 vrf description customer
  rd 1:2
  route-target both 1:2
  route-target import 1:1

In a multipath instance PE1 will install the Equal Cost route with rd 1:1
first, using 1:2 as a secondary path only. Opposite on PE2. 

2)
Could use different VRF's. Just like dual carriers. A key concern is a dual
failure, site 1 on network 1 and site 2 on network 2. The customer will need
to provide a path between the two networks via one of their sites.

David

--
http://dcp.dcptech.com


> -----Original Message-----
> From: jack daniels [mailto:[email protected]]
> Sent: Thursday, March 25, 2010 2:41 PM
> To: David Prall
> Cc: [email protected]
> Subject: Re: [c-nsp] PFR Question
> 
> Hi David ,
> 
> thanks man I got the basic idea :)
> 
> 1) but please explain in more detail this
> 
> Single VRF, 2 distinct RD's. The VRF imports both, exports one. The
> RD's are
> different so that multipath can be used within the core typically. But
> in
> this case they wouldn't use multipath and the local RD would be used as
> the
> determining factor on import of which route is installed first.??????
> 
> 
> 2) Also if I use diffrent VRF for CE4---CE2 path that will also work -
> ??
> 
> 
> On Thu, Mar 25, 2010 at 11:57 PM, David Prall <[email protected]> wrote:
> 
> 
>       If the link goes away, then the update should be pretty quick.
> 
>       Single VRF, 2 distinct RD's. The VRF imports both, exports one.
> The RD's are
>       different so that multipath can be used within the core
> typically. But in
>       this case they wouldn't use multipath and the local RD would be
> used as the
>       determining factor on import of which route is installed first.
> 
>       The local CE (CE3) is probing for the subnet at CE1. When it is
> no longer
>       reachable by CE3 it will move the route to CE4. As long as CE4 is
> using CE2
>       as the path via the cloud then no issue.
> 
> 
>       David
> 
>       --
>       http://dcp.dcptech.com <http://dcp.dcptech.com/>
> 
> 
>       > -----Original Message-----
>       > From: jack daniels [mailto:[email protected]]
> 
>       > Sent: Thursday, March 25, 2010 2:19 PM
>       > To: David Prall
>       > Cc: [email protected]
>       > Subject: Re: [c-nsp] PFR Question
>       >
> 
>       > If a single carrier, then the CE4/CE2 path needs to be via
>       > a second RD so that the paths within the carrier are preferred
> and the
>       > same
>       > will happen.????
>       > DO YOU mean we need to have diifrent vrf on secondry end to end
> path.
>       >
>       > I didnt get this if single carrier as link PE1 and CE1 link
> fails
>       > ....CE3 send traffic for X.X.X.X to PE3.PE3 still has next hop
> in its
>       > vrf table as PE1....
>       >
>       >
>       >
>       >
>       > Please help me as still confused if two carriers , how will
> this
>       > hhappen
>       >
>       >
>       > On Thu, Mar 25, 2010 at 11:29 PM, David Prall <[email protected]>
> wrote:
>       >
>       >
>       >       Is MPLS Domain a single carrier, or two carriers. If two
> carriers
>       > then the
>       >       CE3/CE4 site will see that they can't reach via CE3/CE1
> path and
>       > switch over
>       >       to CE4/CE2 path. If a single carrier, then the CE4/CE2
> path needs
>       > to be via
>       >       a second RD so that the paths within the carrier are
> preferred
>       > and the same
>       >       will happen. PfR is providing end-to-end reachability
> information
>       > in this
>       >       case, and based on that changing the local routing table.
>       >
>       >       David
>       >
>       >
>       >       --
> 
>       >       http://dcp.dcptech.com <http://dcp.dcptech.com/>
> <http://dcp.dcptech.com/>
> 
>       >
>       >
>       >       > -----Original Message-----
>       >
>       >       > From: jack daniels [mailto:[email protected]]
>       >       > Sent: Thursday, March 25, 2010 1:07 PM
>       >       > To: David Prall
>       >       > Cc: [email protected]
>       >       > Subject: Re: [c-nsp] PFR Question
>       >       >
>       >
>       >       > But if you have --
>       >       >
>       >       >
>       >       >                       |CE1--------PE1
>       >       > PE3--------CE3
>       >       >  X.X.X.X---------|                 --------------------
> MPLS
>       > DOMAIN-----
>       >       > --------------
>       >       >                      |  CE2--------PE2
>       >       > PE4--------CE4
>       >       >
>       >       >
>       >       > Now my primary link is CE1-PE1 and secondary is CE2-PE2
>       >       > If my CE1-PE1 goes down i route traffic via CE2-
> PE2<<<<<<I
>       > understand
>       >       > this ok...
>       >       >
>       >       > when traffic from CE3 for X.X.X.X reaches PE3 , next
> hop is
>       > still PE1 (
>       >       > as MPBGP has not converged so fast in MPLS domain of
> SP) ...so
>       > how will
>       >       > traffic be forwareded , as PFR claims 3 sec.
>       >       >
>       >       >
>       >       > On Thu, Mar 25, 2010 at 10:16 PM, David Prall
> <[email protected]>
>       > wrote:
>       >       >
>       >       >
>       >       >       PfR is a unidirectional feature. The router on
> the other
>       > end
>       >       > needs to be
>       >       >       configured with PfR as well in order to have
>       > bidirectional
>       >       > visibility.
>       >       >       Typically the master controller will be local to
> the
>       > site.
>       >       >
>       >       >       --
>       >
>       >       >       http://dcp.dcptech.com <http://dcp.dcptech.com/>
> <http://dcp.dcptech.com/>
>       > <http://dcp.dcptech.com/>
>       >
>       >       >
>       >       >
>       >       >
>       >       >       > -----Original Message-----
>       >       >       > From: [email protected]
> [mailto:cisco-
>       > nsp-
>       >       >       > [email protected]] On Behalf Of jack
> daniels
>       >       >       > Sent: Thursday, March 25, 2010 12:35 PM
>       >       >       > To: [email protected]
>       >       >       > Subject: Re: [c-nsp] PFR Question
>       >       >       >
>       >       >       > dear guys,
>       >       >       >
>       >       >       > is my mail being delivered to group as no one
> replied.
>       >       >       >
>       >       >       > On Wed, Mar 24, 2010 at 11:42 PM, jack daniels
>       >       >       > <[email protected]>wrote:
>       >       >       >
>       >       >       > > Hi Network champs,
>       >       >       > >
>       >       >       > > I'm stuck in understanding of PFR . Docs say
> it
>       > converges in
>       >       > 3 sec (
>       >       >       > for
>       >       >       > > realtime traffic VOICE )...
>       >       >       > >
>       >       >       > > I understand you can send traffic out
> secondry link
>       > but what
>       >       > about
>       >       >       > traffic
>       >       >       > > which has to come back from remote end ( for
> which SP
>       > has not
>       >       >       > converged).
>       >       >       > >
>       >       >       > > But if you have --
>       >       >       > >
>       >       >       > >
>       >       >       > >
>       >       >       > > |CE1--------PE1
>       >       >       > > PE3--------CE3
>       >       >       > >  X.X.X.X---------|                 ----------
> --------
>       > --MPLS
>       >       >       > > DOMAIN-------------------
>       >       >       > >                      |  CE2--------PE2
>       >       >       > > PE4--------CE4
>       >       >       > >
>       >       >       > >
>       >       >       > > Now my primary link is CE1-PE1 and secondary
> is CE2-
>       > PE2
>       >       >       > > If my CE1-PE1 goes down i route traffic via
> CE2-
>       > PE2<<<<<<I
>       >       > understand
>       >       >       > this
>       >       >       > > ok...
>       >       >       > >
>       >       >       > >
>       >       >       > > BUT MY QUESTION IS -
>       >       >       > >
>       >       >       > > PE3 and PE4 ( for this VRF) still has NOW
> converged
>       > the BGP
>       >       > and still
>       >       >       > for
>       >       >       > > it next hop for X.X.X.X is PE1. So how fwd
> can happen
>       > in 3
>       >       > sec untill
>       >       >       > > Service providers all routers dont converge
> and
>       > understand
>       >       > that CE1-
>       >       >       > PE1 link
>       >       >       > > is down.
>       >       >       > >
>       >       >       > >
>       >       >       > > Regards
>       >       >       > >
>       >       >       > >
>       >       >
>       >       >       > _______________________________________________
>       >       >       > cisco-nsp mailing list  cisco-
> [email protected]
>       >       >       > https://puck.nether.net/mailman/listinfo/cisco-
> nsp
>       >       >       > archive at
> http://puck.nether.net/pipermail/cisco-nsp/
>       >       >
>       >       >
>       >       >
>       >
>       >
>       >
>       >
> 
> 
> 
> 


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