From: Brad Caplan (bradcaplan@xxxxxxxxx)
Date: Mon Nov 05 2001 - 14:02:40 GMT-3
As mentioned below, I have layer 2 connectivity - I
can ping all the serial interfaces from any router. I
am having problems with L3 (RIP and split horizon.)
I am using map statements on the spoke routers. I can
only see all networks in the route table of the hub if
I use subinterfaces (Point-to-Point) on the spoke
routers. Is there a way to do this without using sub
interfaces and point-to-point connections?
I thought I could just use 'no ip split-horizon' on
the hub, but that does not seem to work.
--- Craig King <cking007@hotmail.com> wrote:
> I may be repeating what Parry is saying, but I'll
> say it anyway:
>
> On the spoke routers, are you using inverse-arp or
> frame maps? Assuming you
> are using frame maps, have you included an entry for
> each spoke router
> mapping the remote spoke to the hub's dlci? Without
> this, the router won't
> know what dlci to send the traffic along to.
>
> Also, enable frame-relay debugging (debug frame
> packet or debug frame
> verbose) and check to see what errors you see on the
> originating spoke side.
> Encapsulation failed messages indicate no
> ip-to-dlci mapping exists for
> the router to forward the frame over. Enable this
> on both spokes and the
> hub. For the ping to work properly, you will need
> the return path to be set
> up properly as well.
>
> Since the serial interfaces are all part of the same
> logical network, remove
> L3 (RIP and split-horizon) from the equation and
> just troubleshoot L2 and
> get that working - every serial interface should be
> abe to ping each other.
> When that's working, then you can introduce L3 and
> deal with split-horizon
> issues.
>
> HTH,
> CK
>
>
> >From: "Chua, Parry" <Parry.Chua@compaq.com>
> >Reply-To: "Chua, Parry" <Parry.Chua@compaq.com>
> >To: "'Brad Caplan'" <bradcaplan@yahoo.com>,
> ccielab@groupstudy.com
> >Subject: RE: Basic Frame Relay, RIP, and Split
> Horizon Question
> >Date: Mon, 5 Nov 2001 15:15:20 +0800
> >
> >Hi,
> >
> >When you create a p2p sub interface, it behave like
> a orginal physical
> >serial interface, ie
> >sp is enabled. Looking at your topology, it is NOT
> a fully mesk FR, you
> >must
> >ensure that
> >spoke can reach the other spoke. In typical case,
> you make use of
> >spoke->hub->spoke for layer 2 reachability. Each
> router must has a path to
> >other router.
> >
> >Next is the routing update(layer 3). From your
> topology, sp must be enable
> >on hub and usually should be disable on spoke.
> Reason is hub has to act
> >upon
> >for the spoke to pass the routing update, for
> example, update send from R2
> >should receive by R1, R3 to R6, the path from R2
> routing update send to
> >R1(hub), later R1(hub) should forward this update
> to R3...R6. R1 using one
> >(common) interface to reach R2 to R6, if sp is
> enable, it will not forward
> >the update learn from R2 to R6 out from the same
> interface.( of course if
> >you create multiple sub interface at R1 will
> resolve this problem but it
> >also mean you has to create seperate subnet).
> >
> >What will happen is route update send from R2 to R6
> will be send back to
> >then again with additional hop count. You can
> control by filtering if
> >necessary. If sp is diable on R2 to R6
> >( default FR on main intercface), then you should
> enable SP on spoke router
> >to prevent it from sending unnecessary update back
> to R1.
> >
> > > Parry Chua
> > > COMPAQ Computer Asia Pte Ltd
> > > Customer Services - APD
> > > Tel : +65-395-1856
> > > Fax : +65-3951878
> > > Email : parry.chua@compaq.com
> > >
> > >
> >
> >
> >-----Original Message-----
> >From: Brad Caplan [mailto:bradcaplan@yahoo.com]
> >Sent: Monday, November 05, 2001 2:45 PM
> >To: Chua, Parry; ccielab@groupstudy.com
> >Subject: RE: Basic Frame Relay, RIP, and Split
> Horizon Question
> >
> >
> >There is connectivity to all serial interfaces. R1
> can
> >ping all spokes and vice versa. Unfortunately, I
> can't
> >seem to get RIP to advertise the ethernet interface
> >network addresses. All spokes can ping the ethernet
> >interface of R1, but not the ehternet interfaces of
> >the other spokes.
> >
> >It seems like the problem is a split horizon issue
> >whereby R1 is not forwarding the spoke ethernet
> >network addresses. I can get it to work if I use
> sub
> >interfaces (point-to-point) but am wondering if
> there
> >is any other way.
> >
> >Brad
> >
> >
> >
> >--- "Chua, Parry" <Parry.Chua@compaq.com> wrote:
> > > Hi,
> > >
> > > You need to verify the datalink(layer2)
> reachability
> > > first using network
> > > layer address to verify. From your topology, it
> is
> > > assume that R1 is the
> > > hub, R2 to R6 are spokes. It is assume that R1
> has 5
> > > dlci to reach R2 to R6.
> > > It is assume that R2 to R6 each has one dlci and
> can
> > > only reach R1. The
> > > first step you need to do is to ensure that
> R1(hub)
> > > can ping (spokes)R2 to
> > > R6 and vice versa. Next you need to verify R2 to
> R6
> > > (spoke to spoke). Afther
> > > this is done.
> > > Next it what routing protocols to run in this
> cloud,
> > > each has problem to
> > > resolve.
> > >
> > >
> > >
> > > > Parry Chua
> > > >
> > >
> > >
> > > -----Original Message-----
> > > From: Brad Caplan [mailto:bradcaplan@yahoo.com]
> > > Sent: Monday, November 05, 2001 9:57 AM
> > > To: ccielab@groupstudy.com
> > > Subject: Basic Frame Relay, RIP, and Split
> Horizon
> > > Question
> > >
> > >
> > > I have a Hub and Spoke configuration setup as
> > > follows:
> > >
> > > R1------FR-------R2
> > > |
> > > --------R3
> > > |
> > > --------R5
> > > |
> > > --------R6
> > >
> > > All of the router's serial connections are in
> the
> > > 10.1.1.x/24 network. Each router's ethernet
> > > connection
> > > is in a different class A network. Each router
> is
> > > running RIP.
> > >
> > > I can only ping the LAN interfaces of all
> > > routers if I use point-to-point subinterfaces on
> the
> > > spoke routers.
> > >
> > > Is it possible to achieve this same connectivity
> > > without using sub-interfaces? I tried using the
> 'no
> > > ip
> > > split-horizon' command on the serial interface
> of
> > > the
> > > hub router, (R1) but that does not seem to help.
> > >
> > > Thanks,
> > > Brad
> > >
> > >
> > >
> > >
This archive was generated by hypermail 2.1.4 : Fri Jun 21 2002 - 06:45:04 GMT-3