To clear dynamically created Frame Relay maps that are created using Inverse ARP, use the clear frame-relay inarp command, as shown in Figure 1.
A final task is to confirm whether the frame-relay inverse-arp command resolved a remote IPv4 address to a local DLCI. Use the show frame-relay map command to display the current map entries and information about the connections. Figure 2 shows output from router R3 with a previous Frame Relay configuration on the physical interface, without the use of subinterfaces. Inverse ARP is enabled by default for IPv4. Frame Relay for IPv6 uses Inverse Neighbor Discovery (IND) to obtain a Layer 3 IPv6 address from a Layer 2 DLCI.
The output shows the following information:
- 10.1.1.9 is the IPv4 address of the remote router, dynamically learned via the Inverse ARP process.
- 302 is the decimal value of the local DLCI number.
- 0x12E is the hex conversion of the DLCI number, 0x12E = 302 decimal.
- 0x48E0 is the value as it would appear on the wire because of the way the DLCI bits are spread out in the address field of the Frame Relay frame.
- Broadcast/multicast is enabled on the PVC.
- LMI type is cisco.
- PVC status is active.
When an Inverse ARP request is made, the router updates its map table with three possible LMI connection states. These states are:
- ACTIVE - Indicates a successful end-to-end (DTE to DTE) circuit.
- INACTIVE - Indicates a successful connection to the switch (DTE to DCE) without a DTE detected on the other end of the PVC. This can occur due to incorrect configuration on the switch.
- DELETED - Indicates that the DTE is configured for a DLCI that the switch does not recognize as valid for that interface.