Frame-Relay Inverse-Arp Command on CISCO Router/Switch

Command

Frame-Relay Inverse-Arp

Use

This command enables frame-relay inverse-arp. Frame-relay uses inverse-map to dynamically learn remote IP addresses and its local DLCIs.

Syntax

Router(config-if)#frame-relay inverse-arp
OR
Router(config-if)#frame-relay inverse-arp ip <dlci>

Example

Frame-Relay Inverse-Arp Command on CISCO Router/Switch 1

In this example we will configure R4 to use frame-relay.

R4(config)#int s0/0
R4(config-if)#encapsulation frame-relay
R4(config-if)#ip add 10.4.4.4 255.255.255.0
R4(config-if)#no shut

Next, we will configure R1 to use frame-relay.

R1(config)#int s1/0
R1(config-if)#encapsulation frame-relay
R1(config-if)#ip add 10.4.4.1 255.255.255.0
R1(config-if)#no shut

After, we do the same to R3.

R3(config)#int s1/0
R3(config-if)#encapsulation frame
R3(config-if)#encapsulation frame-relay
R3(config-if)#ip add 10.4.4.3 255.255.255.0
R3(config-if)#no shut

Now we use show frame-relay mapping to verify that R4 has learned about the other links via inverse-arp. We also check to see that we can ping.

R4(config-if)#do sh frame map
Serial0/0 (up): ip 10.4.4.1 dlci 401(0x191,0x6410), dynamic,
broadcast,, status defined, active
Serial0/0 (up): ip 10.4.4.3 dlci 403(0x193,0x6430), dynamic,
broadcast,, status defined, active
R4(config-if)#do ping 10.4.4.4

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.4.4.4, timeout is 2 seconds:
..
Success rate is 0 percent (0/2)
R4(config-if)#do ping 10.4.4.1

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.4.4.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 8/32/84 ms
R4(config-if)#do ping 10.4.4.3

Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 10.4.4.3, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 8/37/68 ms