RE: Frame-relay inv-arp

Anantha,

Since that command "frame-relay inverse ip <DLCI>" is the default, it will not show up under the interface when you enter it. The "no frame-relay inverse-arp" disables inverse-arp completely on the main interface. So, the preferred method is to remove the INARP's on the unused DLCI and allow it only over the specified DLCI.

Debugs:

Rack1R2(config-if)#do show fram pvc | i DLCI
DLCI = 201, DLCI USAGE = UNUSED, PVC STATUS = ACTIVE, INTERFACE = Serial0/3/0
DLCI = 203, DLCI USAGE = UNUSED, PVC STATUS = ACTIVE, INTERFACE = Serial0/3/0
DLCI = 204, DLCI USAGE = UNUSED, PVC STATUS = ACTIVE, INTERFACE = Serial0/3/0
DLCI = 205, DLCI USAGE = UNUSED, PVC STATUS = ACTIVE, INTERFACE = Serial0/3/0
DLCI = 213, DLCI USAGE = UNUSED, PVC STATUS = INACTIVE, INTERFACE = Serial0/3/0
Rack1R2(config-if)#
*Apr 27 01:08:18.702: Serial0/3/0: broadcast search
*Apr 27 01:08:18.702: Serial0/3/0:encaps failed on broadcast for link 7(IP)
*Apr 27 01:08:18.702: Serial0/3/0: broadcast search
*Apr 27 01:08:18.702: Serial0/3/0:encaps failed on broadcast for link 7(IP)
Rack1R2(config-if)#
*Apr 27 01:08:24.270: Serial0/3/0: broadcast search
*Apr 27 01:08:24.270: Serial0/3/0:encaps failed on broadcast for link 7(IP)
*Apr 27 01:08:24.594: Serial0/3/0(i): dlci 205(0x30D1), pkt type 0x800, datagramsize 536
*Apr 27 01:08:24.770: Serial0/3/0(i): dlci 205(0x30D1), pkt type 0x800, datagramsize 156

No INARPs, just standard LMI updates, here is the interface with your configuration applied, the INARP command does not show up:

interface Serial0/3/0
 ip address 155.1.0.2 255.255.255.0
 ip rip advertise 10
 encapsulation frame-relay
 no frame-relay inverse-arp
end

Debugs after enabling INARP, but only allowing a single DLCI:

Rack1R2(config-if)#no fram inv ip 203
Rack1R2(config-if)#no fram inv ip 204
Rack1R2(config-if)#no fram inv ip 205
Rack1R2(config-if)#no fram inv ip 213
Rack1R2(config-if)#no shut
Rack1R2(config-if)#
*Apr 27 01:09:58.418: Serial0/3/0(o): dlci 201(0x3091), pkt encaps 0x0300 0x8000 0x0000 0x806 (ARP), datagramsize 34
*Apr 27 01:09:58.418: FR: Sending INARP Request on interface Serial0/3/0 dlci 201 for link 7(IP)
*Apr 27 01:09:58.518: broadcast dequeue
*Apr 27 01:09:58.518: Serial0/3/0(o):Pkt sent on dlci 201(0x3091), pkt encaps 0x300 0x8000 0x0 0x806 (ARP), datagramsize 34

And then after adding the same commands on R1, the INARP process works as expected:

*Apr 27 01:12:28.374: FR: Sending INARP Reply on interface Serial0/3/0 dlci 102 for link 7(IP)
Rack1R1(config-if)#
*Apr 27 01:12:30.050: Serial0/3/0: broadcast search
*Apr 27 01:12:30.050: Serial0/3/0(o): dlci 102(0x1861), pkt type 0x800(IP), datagramsize 296
*Apr 27 01:12:30.054: broadcast dequeue
*Apr 27 01:12:30.054: Serial0/3/0(o):Pkt sent on dlci 102(0x1861), pkt type
0x800(IP), datagramsize 296

Rack1R1(config-if)#do show fram map
Serial0/3/0 (up): ip 155.1.0.2 dlci 102(0x66,0x1860), dynamic,
              broadcast,
              CISCO, status defined, active

HTH

-ryan

-----Original Message-----
From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of Anantha Subramanian Natarajan
Sent: Sunday, April 26, 2009 8:59 PM
To: ccielab_at_groupstudy.com
Subject: Frame-relay inv-arp

Hi All,

  I am trying to understand one of the excercise in the IE oldver
versions,the requirement is to configure frame-relay on main interface
between r3 and r4 and to use inv-arp for ip to dlci mapping .It asso
mentions not to allow frame-relay inv-arp request out anyother DLCI's
assigned to the interface.

R3 -314-FR Cloud -- 413 ---R4

The solution provides similar to this

R3:
interface Serial1/1
encapsulation frame-relay
no frame-relay inverse-arp ip 311
no frame-relay inverse-arp ip 312
no frame-relay inverse-arp ip 315
R4:
interface Serial0/0
encapsulation frame-relay
no frame-relay inverse-arp ip 401
no frame-relay inverse-arp ip 402
no frame-relay inverse-arp ip 403
no frame-relay inverse-arp ip 405

I am trying to understand whether the below solution is also right.Please
comment on it.

 R3:
interface Serial1/1
encapsulation frame-relay
no frame-relay inverse-arp
frame-relay inverse-arp ip 314

R4:
interface Serial0/0
encapsulation frame-relay
no frame-relay inverse-arp
frame-relay inverse-arp ip 413
Thanks

Regards
Anantha Subramanian Natarajan

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Received on Sun Apr 26 2009 - 21:23:55 ART