将路由器连接起来如下图：
接下来是为路由器添加模块（注意要关电添加）：
下面配置路由器A的接口IP：
Router#
Router#config
Configuring from terminal, memory, or network [terminal]?
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#in
Router(config)#interface se
Router(config)#interface serial 1/1
Router(config-if)#ip ad
Router(config-if)#ip address 192.168.1.1 255.255.255.0
Router(config-if)#co
Router(config-if)#cl
Router(config-if)#clock ?
rate Configure serial interface clock speed
Router(config-if)#clock ra
Router(config-if)#clock rate 64000
Router(config-if)#no sh
Router(config-if)#no shutdown
%LINK-5-CHANGED: Interface Serial1/1, changed state to down
Router(config-if)#
%LINK-5-CHANGED: Interface Serial1/1, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1/1, changed state to up
00:14:54: %OSPF-5-ADJCHG: Process 2, Nbr 10.10.11.1 on Serial1/1 from LOADING to FULL, Loading Done
Router(config-if)#
下面配置路由器B的接口IP：
Router#config
Configuring from terminal, memory, or network [terminal]?
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#in
Router(config)#interface se 1/0
Router(config-if)#ip ad
Router(config-if)#ip address 192.168.1.2 255.255.255.0
Router(config-if)#no sh
Router(config-if)#no shutdown
%LINK-5-CHANGED: Interface Serial1/0, changed state to up
Router(config-if)#
%LINEPROTO-5-UPDOWN: Line protocol on Interface Serial1/0, changed state to up
01:07:29: %OSPF-5-ADJCHG: Process 2, Nbr 10.10.10.1 on Serial1/0 from LOADING to FULL, Loading Done
Router(config-if)#
接下来进行路由器A环回接口的配置：
Router>en
Router#config
Configuring from terminal, memory, or network [terminal]?
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#in
Router(config)#interface lo
Router(config)#interface loopback ?
<0-2147483647> Loopback interface number
Router(config)#interface loopback 0
%LINK-5-CHANGED: Interface Loopback0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Loopback0, changed state to up
Router(config-if)#ip ad
Router(config-if)#ip address 10.10.10.1 255.255.255.0
Router(config-if)#
下一步进行路由器B环回接口的配置：
Router>en
Router#config
Configuring from terminal, memory, or network [terminal]?
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#in lo 0
%LINK-5-CHANGED: Interface Loopback0, changed state to up
%LINEPROTO-5-UPDOWN: Line protocol on Interface Loopback0, changed state to up