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Frame Relay Configuration 265
information. For IOS Software Release 11.2 and later, you need not configure the LMI type. To
disable LMI completely, use the no keepalive command to cease to transmit and receive LMI.
However, keepalives must also be disabled at the switch.
At this point, you can configure address mapping, if necessary. In the case of point-to-point
connections, mapping of protocol addresses to DLCIs is dynamic and requires no intervention
(usually). However, if point-to-multipoint connections are in use, manual mapping is necessary.
Mapping is quite the same from protocol to protocol, so IP was the only one discussed in this
section of the chapter. Figure 9-7 depicts a sample topology.
Figure 9-7
Configuration Topology Example
Figure 9-7 shows three point-to-point subinterfaces that require the creation of three individual
subnets. The central router in this configuration is RouterA.
Although Example 9-1 covered the basic configuration for RouterA, the PVCs still need to be
defined. In addition, because Example 9-1 already uses point-to-point interfaces, the only thing
lacking is the DLCI, which the configuration in Example 9-2 provides.
Example 9-2
Frame Relay Subinterfaces Configuration (Point-to-Point)
RouterA(config)#interface serial 0
RouterA(config-if)#encapsulation frame-relay
RouterA(config-if)#interface serial 0.1 point-to-point
RouterA(config-subif)#ip address 10.1.1.1 255.255.255.0
RouterA(config-subif)#frame-relay interface-dlci 16
RouterA(config-fr-dlci)#interface serial 0.2 point-to-point
RouterA(config-subif)#ip address 10.1.2.1 255.255.255.0
RouterA(config-subif)#frame-relay interface-dlci 17
RouterA(config-fr-dlci)#interface serial 0.3 point-to-point
RouterA(config-subif)#ip address 10.1.3.1 255.255.255.0
RouterA(config-subif)#frame-relay interface-dlci 18
S0.1
S0.2
S0.3
A
D
C
B
DLCI=18
DLCI=16
DLCI=17
Frame Relay
cloud
S0 IP=10.1.1.2/24
DLCI=20
S0 IP=10.1.2.2/24
DLCI=20
S0 IP=10.1.3.2/24
DLCI=20
S0.1 IP=10.1.1.1/24
S0.2 IP=10.1.2.1/24
S0.3 IP=10.1.3.1/24