frame relay two point to point using same subnet ip;s

From: Imran Ali <immrccie_at_gmail.com>
Date: Fri, 27 Sep 2013 17:02:53 +0300

Hi ,

i have a task and i am required to configure two ip's from same
subnet , on two different frame relay interfaces.

on a physical interface this is not possible , but on a point to point
interface ..we can apply ip's from same subnet .

all i need is to configure OSPF network type " point to mutipoint "
and ping all interfaces

   R2======== R1 ============R3
spoike------------hub----------------spoke

*on R1*
 interface Serial0/0.12 point-to-point
 ip address 172.16.124.1 255.255.255.0
 frame-relay interface-dlci 102

R1#r s0/0.13
Building configuration...

Current configuration : 119 bytes
!
interface Serial0/0.13 point-to-point
 ip address 172.16.124.4 255.255.255.0
 frame-relay interface-dlci 103

*on R2*

!
interface Serial0/0
 ip address 172.16.124.2 255.255.255.0
 encapsulation frame-relay
 ip ospf network point-to-point
 serial restart-delay 0
 frame-relay map ip 172.16.124.1 201 broadcast
 frame-relay map ip 172.16.124.4 201
 no frame-relay inverse-arp

*on R3*

interface Serial0/0
 ip address 172.16.124.3 255.255.255.0
 encapsulation frame-relay
 i
 frame-relay map ip 172.16.124.1 301 broadcast
 frame-relay map ip 172.16.124.4 301 broadcast
 no frame-relay inverse-arp

As you can see spokes have mappings for both ip's of hub.

now lets try to ping the spokes from hub

R1#ping 172.16.124.2

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.124.2, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
R1#ping 172.16.124.3

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.124.3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 1/21/76 ms

lets try once again

R1#ping 172.16.124.2

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.124.2, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
R1#ping 172.16.124.2

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.124.2, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
R1#ping 172.16.124.3

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.124.3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/26/60 ms

*so it seems R2 is not rechable and R3 is always replying *

on R3 ...let turn debug
R3#show debug
Generic IP:
  IP packet debugging is on
R3#

lets do " no service timestamps " so that actual message is more
apparent

R1#ping 172.16.124.2 repeat 1

Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 172.16.124.2, timeout is 2 seconds:
.

IP: tableid=0, s=172.16.124.1 (Serial0/0), d=172.16.124.2 (Serial0/0),
routed via RIB
*IP: s=172.16.124.1 (Serial0/0), d=172.16.124.2 (Serial0/0), len 100,
redirected*
IP: tableid=0, s=172.16.124.3 (local), d=172.16.124.1 (Serial0/0), routed
via FIB
IP: s=172.16.124.3 (local), d=172.16.124.1 (Serial0/0), len 56, sending
IP: s=172.16.124.1 (Serial0/0), d=172.16.124.2 (Serial0/0), g=172.16.124.2,
len 100, forward
*IP: s=172.16.124.1 (Serial0/0), d=172.16.124.2 (Serial0/0), len 100,
encapsulation failed
*

adding ...spoke to spoke statements
R2(config)#int s0/0
R2(config-if)#fram
R2(config-if)#frame-relay map ip 172.16.124.3 201

R3(config)#int s0/0
R3(config-if)#fram
R3(config-if)#frame-relay map ip 172.16.124.2 301 b

*R1#debug frame-relay packet
Frame Relay packet debugging is on

*R1#ping 172.16.124.2 repeat 1

Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 172.16.124.2, timeout is 2 seconds:

*Serial0/0.13(o): dlci 103(*0x1871), pkt type 0x800(IP), datagramsize 104
Serial0/0(i): dlci 103(0x1871), pkt type 0x800, datagramsize 104.
Success rate is 0 percent (0/1)
R1#
R1#
R1#ping 172.16.124.3 repeat 1

Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 172.16.124.3, timeout is 2 seconds:
!
Success rate is 100 percent (1/1), round-trip min/avg/max = 40/40/40 ms
R1#
Serial0/0(i): dlci 102(0x1861), pkt type 0x800, datagramsize 80
Serial0/0(i): dlci 103(0x1871), pkt type 0x800, datagramsize 80
Serial0/0(i): dlci 103(0x1871), pkt type 0x800, datagramsize 80
Serial0/0(i): dlci 103(0x1871), pkt type 0x800, datagramsize 80
R1#*
Serial0/0.13(o): dlci 103(0x1871), pkt type 0x800(IP), datagramsize 104
Serial0/0(i): dlci 103(0x1871), pkt type 0x800, datagramsize 104*

it seems now R1 is only using one DLCI to reach both spokes ...ie 103

but strangely when i add ospf process on hub routers ...both spoke
become adjacent

R1(config-router)#network 172.16.124.1 0.0.0.0 a 0
R1(config-router)#ne
%OSPF-5-ADJCHG: Process 1, Nbr 172.16.124.2 on Serial0/0.12 from LOADING to
FULL, Loading Done
R1(config-router)#net
R1(config-router)#network 172.16.124.4 0.0.0.0 a 0
R1(config-router)#exit
R1(config)#exit
R1#
%OSPF-5-ADJCHG: Process 1, Nbr 172.16.124.3 on Serial0/0.13 from LOADING to
FULL, Loading Done
%SYS-5-CONFIG_I: Configured from console by console
R1#o

*Neighbor ID Pri State Dead Time Address Interface
172.16.124.3 0 FULL/ - 00:00:36 172.16.124.3
Serial0/0.13
172.16.124.2 0 FULL/ - 00:00:36 172.16.124.2
Serial0/0.12*
R1#

but even now i cant ping R2 ....

R1#ping 172.16.124.2

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.124.2, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
R1#ping 172.16.124.2 so
R1#ping 172.16.124.2 source 172.16.124.4

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.124.2, timeout is 2 seconds:
Packet sent with a source address of 172.16.124.4
.....
Success rate is 0 percent (0/5)
R1#ping 172.16.124.3

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.124.3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/36/88 ms
R1#ping 172.16.124.3 source 172.16.124.4

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.124.3, timeout is 2 seconds:
Packet sent with a source address of 172.16.124.4
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/16/44 ms
R1#se
Interface IP-Address OK? Method Status
Protocol
Serial0/0.12 172.16.124.1 YES manual up
up
Serial0/0.13 172.16.124.4 YES manual up
up

Can any body try out the same senario ... and post it

to summarize

*R2#o*

Neighbor ID Pri State Dead Time Address Interface
172.16.124.4 0 FULL/ - 00:00:31 172.16.124.1 Serial0/0
R2#ping 172.16.124.4

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.124.4, timeout is 2 seconds:
.....
Success rate is 0 percent (0/5)
R2#ping 172.16.124.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.124.1, timeout is 2 seconds:

clear ip ospf process..

*Mar 1 01:27:28.571: %OSPF-5-ADJCHG: Process 1, Nbr 172.16.124.4 on
Serial0/0 from FULL to DOWN, Neighbor Down: Interface down or detached
*Mar 1 01:27:29.099: %OSPF-5-ADJCHG: Process 1, Nbr 172.16.124.4 on
Serial0/0 from LOADING to FULL, Loading Done
R2#o

Neighbor ID Pri State Dead Time Address Interface
172.16.124.4 0 FULL/ - 00:00:38 172.16.124.1 Serial0/0
R2#ping 172.16.124.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 172.16.124.1, timeout is 2 seconds:

.....

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Received on Fri Sep 27 2013 - 17:02:53 ART

This archive was generated by hypermail 2.2.0 : Tue Oct 01 2013 - 06:36:35 ART