OSPF的METRIC計算
接口COST的查看
Router#show ip ospf interface loopback 1
Loopback1 is up, line protocol is up
Internet address is 3.3.3.3/24, Area 0
Process ID 1, Router ID 3.3.3.3, Network Type LOOPBACK, Cost: 1
Loopback interface is treated as a stub Host
計算規則：METRIC是路由條目傳遞方向，經過所有路由器的入接口的COST總和。
COST的修改：
Router(config)#interface loopback 1
Router(config-if)#ip ospf cost 122
每種接口類型的COST值不一樣：
cost計算公式：10^8/接口帶寬
f0/0 cost 1
100000000/100M
100M=100000Kbit=100000000bit
S0/0 cost 64
