RE: OSPF NBMA and P-M interoperable ???

From: Brian Dennis (bdennis@internetworkexpert.com)
Date: Sun Nov 06 2005 - 04:05:45 GMT-3

Victor,
        I'm not 100% sure what you are saying below but if you are
implying that "ip ospf network point-to-multipoint non-broadcast" uses a
DR it's incorrect. There is no DR/BDR with this OSPF network type.

Router#sho run int s0/0
Building configuration...

Current configuration : 183 bytes
!
interface Serial0/0
 ip address 10.1.1.2 255.255.255.0
 encapsulation frame-relay
 ip ospf network point-to-multipoint non-broadcast
 frame-relay map ip 10.1.1.1 201 broadcast
end

Router#sho ip os int s0/0
Serial0/0 is up, line protocol is up
  Internet Address 10.1.1.2/24, Area 0
  Process ID 1, Router ID 10.1.1.2, Network Type POINT_TO_MULTIPOINT,
Cost: 64
  Transmit Delay is 1 sec, State POINT_TO_MULTIPOINT,
  Timer intervals configured, Hello 30, Dead 120, Wait 120, Retransmit 5
    oob-resync timeout 120
    Hello due in 00:00:29
  Index 1/1, flood queue length 0
  Next 0x0(0)/0x0(0)
  Last flood scan length is 1, maximum is 1
  Last flood scan time is 0 msec, maximum is 0 msec
  Neighbor Count is 1, Adjacent neighbor count is 1
    Adjacent with neighbor 10.1.1.1
  Suppress hello for 0 neighbor(s)
Router#sho ip os n

Neighbor ID Pri State Dead Time Address
Interface
10.1.1.1 0 FULL/ - 00:01:54 10.1.1.1
Serial0/0
Router#

HTH,

Brian Dennis, CCIE #2210 (R&S/ISP-Dial/Security)
bdennis@internetworkexpert.com
 
Internetwork Expert, Inc.
http://www.InternetworkExpert.com
Toll Free: 877-224-8987
Direct: 775-745-6404 (Outside the US and Canada)
 

-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
Victor Cappuccio
Sent: Saturday, November 05, 2005 8:33 PM
To: Schulz, Dave; Venkatesh Palani ; nobody@groupstudy.com;
ccielab@groupstudy.com
Subject: Re: OSPF NBMA and P-M interoperable ???

There is other network type like ip ospf network point-to-multipoint
non-broadcast, that would req a DR election using the Neighbor command
on
the HuB and setting the priority on the spokes, this is very useful for
the
hub and spoke topology that requires different BW allocations

I learnt this from Scott Morris (has a broadcast keyword somewhere that
equals DR),

HTH 

---
Victor Cappuccio
cvictor@protokolgroup.com
..O.
....O
OOO
----- Original Message ----- 
From: "Schulz, Dave" <DSchulz@dpsciences.com>
To: "Venkatesh Palani " <kvpalani@gmail.com>; <nobody@groupstudy.com>;
<ccielab@groupstudy.com>
Sent: Sunday, November 06, 2005 12:22 AM
Subject: RE: OSPF NBMA and P-M interoperable ???

> I ran into this issue once before.  It can be very puzzling, because
the
> neighbors fill form a relationship, but the routes will not be
exchanged
> properly.  My understanding is that the non-broadcast and
non-broadcast
(that
> require a DR) will work together.  And, the point-to-point and
> point-to-multipoint will work together (that do not require a DR).
So,
even
> though you form a neighbor relationship, one can never assume that
everything
> is correct.
>
> Dave
>
> -----Original Message-----
> From: nobody@groupstudy.com
> To: ccielab@groupstudy.com
> Sent: 11/5/2005 9:56 PM
> Subject: Re: OSPF NBMA and P-M interoperable ???
>
> Sory guys a bit of correction
>  the correct one is
>
> > Hi Guys,
> > I wonder if NBMA and Point-Multipoint mode are interoperable(I mean
> one
> > interface configured as NBMA and the other configured as
> point-multipoint
> > should they form the neighbours in OSPF ?? ) which I always thought
NO
> > becaue NBMA require DR/BDR where as P-M does not I am afraid if my
> > understanding is wrong .
> > look at this there are 4 routers just three is involved in this
> scenario
> > so consider router 2 (router id 2.2.2.2 <http://2.2.2.2/>) router 3(
> > 3.3.3.3 <http://3.3.3.3/>) and router 4( 4.4.4.4 <http://4.4.4.4/>)
.
> > router 2 and router 3 OSPF is configured as NBMA where as router 4
> serial
> > interafce is configured as aPoint-multipoint. Router 4 forms
Neighbor
> with
> > both Router 2 and router 3 though there are no OSPF routes instaled
in
> the
> > routing table of router 4. The same happens with router 2 and router
3
> they
> > form neighbor relationship with router 4 but no routes from router 4
(
> > meaning the loopback of router 4 which is configured in the OSPF
using
> > network statement) are installed onto the routing table.
> >  any comments..any thoughts ???
> >     From router 4
> > ==================
> >  Serial0/1 is up, line protocol is up
> > Internet Address 137.1.200.4/24 <http://137.1.200.4/24>, Area 0
> > Process ID 1, Router ID 4.4.4.4 <http://4.4.4.4/>, Network Type
> > POINT_TO_MULTIPOINT, Cost: 64
> > Transmit Delay is 1 sec, State POINT_TO_MULTIPOINT,
> > Timer intervals configured, Hello 30, Dead 120, Wait 120, Retransmit
5
> > Hello due in 00:00:09
> > Index 1/2, flood queue length 0
> > Next 0x0(0)/0x0(0)
> > Last flood scan length is 1, maximum is 1
> > Last flood scan time is 0 msec, maximum is 0 msec
> > Neighbor Count is 2, Adjacent neighbor count is 2
> > Adjacent with neighbor 2.2.2.2 <http://2.2.2.2/>
> > Adjacent with neighbor 3.3.3.3 <http://3.3.3.3/>
> > Suppress hello for 0 neighbor(s)
> >
> > Router4#sh ip ospf neighbor
> >
> > Neighbor ID Pri State Dead Time Address Interface
> > 2.2.2.2 <http://2.2.2.2/> 1 FULL/ - 00:01:40
> 137.1.200.2<http://137.1.200.2/>Serial0/1
> > 3.3.3.3 <http://3.3.3.3/> 1 FULL/ - 00:01:30
> 137.1.200.3<http://137.1.200.3/>Serial0/1
> > debug
> >  Router4#
> > *Mar 1 00:20:43.742: IP: s=137.1.200.3 <http://137.1.200.3/>
> (Serial0/1),
> > d=137.1.200.4 <http://137.1.200.4/>, len 76, rcvd
> > 0
> > *Mar 1 00:20:43.742: OSPF: Rcv hello from 3.3.3.3 <http://3.3.3.3/>
> area 0
> > from Serial0/1 137.1.2
> > 00.3
> > *Mar 1 00:20:43.742: OSPF: End of hello processing
> > *Mar 1 00:20:58.153: IP: s=137.1.200.4 <http://137.1.200.4/>
(local),
> d=224.0.0.5
> > <http://224.0.0.5/>(Serial0/1), len 72
> > , sending broad/multicast
> > *Mar 1 00:21:09.788: IP: s=137.1.200.2 <http://137.1.200.2/>
> (Serial0/1),
> > d=137.1.200.4 <http://137.1.200.4/>, len 72, rcvd
> > 0
> > *Mar 1 00:21: 09.788: OSPF: Rcv hello from 2.2.2.2 <http://2.2.2.2/>
> area
> > 0 from Serial0/1 137.1.2
> > 00.2
> > *Mar 1 00:21:09.788: OSPF: End of hello processing
> > *Mar 1 00:21:13.739: IP: s=137.1.200.3
> <http://137.1.200.3/>(Serial0/1),
> > d=137.1.200.4 <http://137.1.200.4/>, len 76, rcvd
> > 0
> > *Mar 1 00:21:13.743: OSPF: Rcv hello from 3.3.3.3 <http://3.3.3.3/>
> area 0
> > from Serial0/1 137.1.2
> > 00.3
> > *Mar 1 00:21: 13.743: OSPF: End of hello processing
> >     config snippet
> >   interface Serial0/1
> > ip address 137.1.200.4 <http://137.1.200.4/>
> 255.255.255.0<http://255.255.255.0/>
> > encapsulation frame-relay
> > ip ospf network point-to-multipoint
> > no arp frame-relay
> > frame-relay map ip 137.1.200.1 <http://137.1.200.1/> 403 broadcast
> > frame-relay map ip 137.1.200.2 <http://137.1.200.2/> 402 broadcast
> > frame-relay map ip 137.1.200.3 <http://137.1.200.3/>403 broadcast
> > frame-relay map ip 172.168.2.1 <http://172.168.2.1/> 403 broadcast
> > frame-relay map ip 172.168.2.2 <http://172.168.2.2/> 403 broadcast
> > no frame-relay inverse-arp
> >  router ospf 1
> > router-id 4.4.4.4 <http://4.4.4.4/>
> > log-adjacency-changes
> > network 44.44.44.0 <http://44.44.44.0/> 0.0.0.255
<http://0.0.0.255/>
> area
> > 4
> > network 137.1.200.0 <http://137.1.200.0/> 0.0.0.255
> <http://0.0.0.255/>area
> 0
> >
> > Router4#sh ip route
> > Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B -
> BGP
> > D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
> > N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
> > E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
> > i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter
> area
> > * - candidate default, U - per-user static route, o - ODR
> > P - periodic downloaded static route
> >
> > Gateway of last resort is not set
> >
> > 137.1.0.0/24 <http://137.1.0.0/24> is subnetted, 2 subnets
> > C 137.1.200.0 <http://137.1.200.0/> is directly connected, Serial0/1
> > C 137.1.4.0 <http://137.1.4.0/> is directly connected, Loopback1
> > 160.1.0.0/24 <http://160.1.0.0/24> is subnetted, 1 subnets
> > C 160.1.1.0 <http://160.1.1.0/> is directly connected, Ethernet0/1
> > 44.0.0.0/24 <http://44.0.0.0/24> is subnetted, 1 subnets
> > C 44.44.44.0 <http://44.44.44.0/> is directly connected, Loopback2
> >
> >   From Router 3
> > =====================
> > Serial0/0 is up, line protocol is up
> > Internet Address 137.1.200.3/24 <http://137.1.200.3/24>, Area 0
> > Process ID 1, Router ID 3.3.3.3 <http://3.3.3.3/>, Network Type
> > NON_BROADCAST, Cost: 64
> > Transmit Delay is 1 sec, State DR, Priority 1
> > Designated Router (ID) 3.3.3.3 <http://3.3.3.3/>, Interface address
> > 137.1.200.3 <http://137.1.200.3/>
> > Backup Designated router (ID) 2.2.2.2 <http://2.2.2.2/>, Interface
> address
> > 137.1.200.2 <http://137.1.200.2/>
> > Timer intervals configured, Hello 30, Dead 120, Wait 120, Retransmit
5
> > Hello due in 00:00:18
> > Index 1/1, flood queue length 0
> > Next 0x0(0)/0x0(0)
> > Last flood scan length is 1, maximum is 3
> > Last flood scan time is 0 msec, maximum is 4 msec
> > Neighbor Count is 3, Adjacent neighbor count is 3
> > Adjacent with neighbor 4.4.4.4 <http://4.4.4.4/>
> > Adjacent with neighbor 2.2.2.2 <http://2.2.2.2/> (Backup Designated
> > Router)
> > Adjacent with neighbor 1.1.1.1 <http://1.1.1.1/>
> > Suppress hello for 0 neighbor(s)
> >
> > router3#sh ip ospf neighbor
> >
> > Neighbor ID Pri State Dead Time Address Interface
> > 4.4.4.4 <http://4.4.4.4/> 1 FULL/DROTHER 00:01:55
> 137.1.200.4<http://137.1.200.4/>Serial0/0
> > 2.2.2.2 <http://2.2.2.2/> 1 FULL/BDR 00:01:50
> 137.1.200.2<http://137.1.200.2/>Serial0/0
> > 1.1.1.1 <http://1.1.1.1/> 1 FULL/DROTHER 00:01:44
> 137.1.200.1<http://137.1.200.1/>Serial0/0
> >
> >   config snippet
> >
> >  interface Serial0/0
> > ip address 137.1.200.3 <http://137.1.200.3/>
> 255.255.255.0<http://255.255.255.0/>
> > encapsulation frame-relay
> > no fair-queue
> > clockrate 128000
> > no arp frame-relay
> > frame-relay map ip 137.1.200.1 <http://137.1.200.1/> 301 broadcast
> > frame-relay map ip 137.1.200.2 <http://137.1.200.2/> 302 broadcast
> > frame-relay map ip 137.1.200.4 <http://137.1.200.4/>304 broadcast
> > no frame-relay inverse-arp
> > frame-relay lmi-type ansi
> >
> > router ospf 1
> > router-id 3.3.3.3 <http://3.3.3.3/>
> > log-adjacency-changes
> > network 33.33.33.0 <http://33.33.33.0/> 0.0.0.255
<http://0.0.0.255/>
> area
> > 0
> > network 137.1.3.0 <http://137.1.3.0/> 0.0.0.255 <http://0.0.0.255/>
> area 3
> > network 137.1.200.0 <http://137.1.200.0/> 0.0.0.255
> <http://0.0.0.255/>area
> 0
> > neighbor 137.1.200.4 <http://137.1.200.4/> priority 1
> > neighbor 137.1.200.2 <http://137.1.200.2/> priority 1
> > neighbor 137.1.200.1 <http://137.1.200.1/> priority 1
> >
> >
>
> Thank you,
> Venkatesh
>
>

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