首先从网上下载gn3这个摸拟器以及cisco路由器的bin.

如图，下面的clouds里添加本地连接，这样表示路由器与本机的网卡桥接。即在R2里的接口设置一个与本机的IP地址同一网段。这样局域网的机就可以与R2通信

R2的配置如下

snmp-server community public RO 读

snmp-server community private RW 写

这两个开启snmp服务。

Router#show running-configBuilding configuration...Current configuration : 623 bytes!version 12.4service timestamps debug datetime msecservice timestamps log datetime msecno service password-encryption!hostname Router!boot-start-markerboot-end-marker!enable password wen!no aaa new-modelmemory-size iomem 5!!ip cefno ip domain lookup!!!!!!!!!!!!!!!!!!interface FastEthernet0/0 ip address 192.168.15.196 255.255.255.0 duplex auto speed auto!ip http server!!!snmp-server community public ROsnmp-server community private RW!!!control-plane!!!!!!!!!line con 0line aux 0line vty 0 4 password wen loginline vty 5 871 password wen login!!endRouter#

 到此已可以用snmp++读取信息了