For this lab, we look at the communication between scar (running Cisco IOS RIPv2 as well in Example 9-7) and callisto (running Zebra RIPv2 in Example 9-8). A combination of the passive-interface and neighbor commands offers granularity in the choice of RIP neighbors that cannot be achieved with the network command alone.
This lab results in unicast RIPv2 communication between the two neighbors, while suppressing multicast messages on 192.168.14.0/24 via the passive-interface command. An additional benefit of the unicast neighbor command is its use for nonbroadcast media such as Frame Relay. The same effect (unicast behavior) can be accomplished with GateD via the sourcegateways <gateway_list> clause in the RIP configuration section.
For even more granularity, Zebra, GateD, and to some extent MRTd offer offset- lists, route maps, distribute lists, access lists, and metric and distance/preference manipulation.
scar# sh running-config
...
router rip
version 2
traffic-share min across-interfaces
redistribute connected
redistribute static
passive-interface Ethernet1
passive-interface Serial0
passive-interface Serial1
passive-interface Serial2
passive-interface Serial3
network 192.168.7.0
network 192.168.14.0
neighbor 192.168.14.1
maximum-paths 2
no auto-summary
...
[root@callisto:~#] cat /usr/local/etc/ripd.conf
...
router rip
redistribute connected
redistribute static
network 192.168.1.0/24
network 192.168.14.0/24
neighbor 192.168.14.254
passive-interface eth0
...