![](https://csdnimg.cn/release/download_crawler_static/1642325/bg5.jpg)
Feb 9 12:43:13.315: RIP: sending request on Loopback0 to 255.255.255.255
Feb 9 12:43:13.323: RIP: received v1 update from 192.168.12.2 on Serial0/0/0
Feb 9 12:43:13.323: 4.0.0.0 in 3 hops
Feb 9 12:43:13.323: 192.168.23.0 in 1 hops
Feb 9 12:43:13.323: 192.168.34.0 in 2 hops
Feb 9 12:43:15.311: RIP: sending v1 flash update to 255.255.255.255 via Loopback0 (1.1.1.1)
Feb 9 12:43:15.311: RIP: build flash update entries
Feb 9 12:43:15.311: network 4.0.0.0 metric 4
Feb 9 12:43:15.311: network 192.168.12.0 metric 1
Feb 9 12:43:15.311: network 192.168.23.0 metric 2
Feb 9 12:43:15.311: network 192.168.34.0 metric 3
Feb 9 12:43:15.311: RIP: sending v1 flash update to 255.255.255.255 via Serial0/0/0
(192.168.12.1)
Feb 9 12:43:15.311: RIP: build flash update entries
Feb 9 12:43:15.311: network 1.0.0.0 metric 1
通过以上输出,可以看到 RIPv1 采用广播更新(255.255.255.255),分别向 Loopback0
和 s0/0/0 发送路由更新,同时从 s0/0/0 接收三条路由更新,分别是 4.0.0.0,度量值是 3
跳;192.168.34.0, 度量值是 2 跳;192.168.23.0,度量值是 1 跳。
【技术要点】
flash update(闪式更新)指的是当网络上某个路径的度量值发生变化,路由器立即
发出更新信息,而不管是否到达常规路由信息更新的周期。
4.2.2 实验 2:被动接口与单播更新
1.实验目的
通过本实验可以掌握:
(1)被动接口的含义、配置和应用场合
(2)单播更新的应用场合和配置
2.拓扑结构
实验拓扑如图 4-2 所示。
图 4-2 配置被动接口
由于以太口 g0/0 和 g0/1 连接主机,不需要向这些接口发送路由更新,所以可以考虑将
路由器的该接口设置为被动接口。