RE: Frame-relay subinterface with same subnet

From: Joseph Saad (joseph.s.saad@gmail.com)
Date: Fri Jul 27 2007 - 07:51:13 ART


Interesting, on the hub you are configuring 2 p-2-p subinterfaces in the
same subnet. Ask yourself how will the router know know which subinterface
to forward the packet on?

It should identify the subinterface based on the subnet information on the
interface. Because on a p-2-p you can't map the destination ip via
frame-relay map ip statement.

You are probably using 102 and 104 alternatively per ping and it is
alternating.

To troubleshoot further.

Debug ip icmp on the receiving end. I doubt that you'll receive only 2 or 3
packets for each 5 pings that you send

-----Original Message-----
From: nobody@groupstudy.com [mailto:nobody@groupstudy.com] On Behalf Of
nagendra kumar
Sent: Friday, July 27, 2007 1:51 PM
To: ccielab@groupstudy.com
Subject: Frame-relay subinterface with same subnet

Hi All,
  
                                                  R1
                 (172.16.124.1/24) - DLCI 104 | (172.16.124.3/24) -
DLCI 102
                                                   |
                                 R4--------------FRSW----------------R2
               (172.16.124.4/24) - DLCI 401 (172.16.124.2/24) - DLCI
201
  
  In the above mentioned topology, I have to configure 2 sub interface in
R1 one to R4 and other to R2 with ip addr from same subnet. The solution
seems to have configured with point-to-point subinterface in R1 physical
interface in other routers.
  
  But when I try it in my setup, I am missing alternate packets. I have
copied the configs below. Can some one throw more lights on how to solve
this issue.
  
  Configuration:
  ===========
  R1#sh run int s5/0.101
  Building configuration...
  
  Current configuration : 120 bytes
  !
  interface Serial5/0.101 point-to-point
   ip address 172.16.124.1 255.255.255.0
   frame-relay interface-dlci 104
  end
  
  R1#sh run int s5/0.102
  Building configuration...
  
  Current configuration : 120 bytes
  !
  interface Serial5/0.102 point-to-point
   ip address 172.16.124.3 255.255.255.0
   frame-relay interface-dlci 102
  end
  
  R1#sh fram pvc 104 | inc STAT
  DLCI = 104, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE =
Serial5/0.101
  R1#sh fram pvc 102 | inc STAT
  DLCI = 102, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE =
Serial5/0.102
  R1#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 60 percent (3/5), round-trip min/avg/max = 40/40/40 ms
  R1#
  R1#sh fram map
  Serial5/0.101 (up): point-to-point dlci, dlci 104(0x68,0x1880), broadcast
            status defined, active
  Serial5/0.102 (up): point-to-point dlci, dlci 102(0x66,0x1860), broadcast
            status defined, active
  R1#
  
  R4#sh run int s5/0
  Building configuration...
  
  Current configuration : 335 bytes
  !
  interface Serial5/0
   ip address 172.16.124.4 255.255.255.0
   encapsulation frame-relay
   serial restart-delay 0
   no dce-terminal-timing-enable
   frame-relay map ip 172.16.124.1 401 broadcast
   no frame-relay inverse-arp IP 402
   no frame-relay inverse-arp IP 403
   no frame-relay inverse-arp IP 405
   no frame-relay inverse-arp IP 502
  end
  
  R4#sh fram pvc | inc 401
  DLCI = 401, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE = Serial5/0
  R4#sh fram map
  Serial5/0 (up): ip 172.16.124.1 dlci 401(0x191,0x6410), static,
                broadcast,
                CISCO, status defined, active
  R4#
  
  R2#
  R2#sh run int s5/0
  Building configuration...
  
  Current configuration : 300 bytes
  !
  interface Serial5/0
   ip address 172.16.124.2 255.255.255.0
   encapsulation frame-relay
   serial restart-delay 0
   no dce-terminal-timing-enable
   frame-relay map ip 172.16.124.3 201 broadcast
   no frame-relay inverse-arp IP 203
   no frame-relay inverse-arp IP 204
   no frame-relay inverse-arp IP 213
  end
  
  R2#sh fram pvc | inc 201
  DLCI = 201, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE = Serial5/0
  R2#sh fram map
  Serial4/3 (up): ip 172.16.25.5 dlci 205(0xCD,0x30D0), dynamic,
                broadcast,
                CISCO, status defined, active
  Serial5/0 (up): ip 172.16.124.3 dlci 201(0xC9,0x3090), static,
                broadcast,
                CISCO, status defined, active
  R2#
  
  Am I missing something here?
  
  Regards,
  Nagendra
  
  
       
---------------------------------
Get the free Yahoo! toolbar and rest assured with the added security of
spyware protection.
       
---------------------------------
Be a better Heartthrob. Get better relationship answers from someone who
knows.
Yahoo! Answers - Check it out.



This archive was generated by hypermail 2.1.4 : Sat Aug 18 2007 - 08:17:42 ART