Dell POWEREDGE M1000E - Manual (Page 917)

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Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
OL-13270-03
Chapter 38 Configuring IP Unicast Routing
Configuring RIP
To disable IP summarization, use the no ip summary-address rip router configuration command.
In this example, the major net is 10.0.0.0. The summary address of 10.2.0.0 overrides the autosummary
address of 10.0.0.0 so that 10.2.0.0 is advertised from interface Gigabit Ethernet port 2, and 10.0.0.0 is
not advertised. In the example, if the interface is still in Layer 2 mode (the default), you must enter the
no switchport interface configuration command before entering the ip address interface configuration
command.
Note If split horizon is enabled, neither autosummary nor interface summary addresses (those configured with
the ip summary-address rip router configuration command) are advertised.
Switch(config)# router rip
Switch(config-router)# interface gigabitethernet1/0/2
Switch(config-if)# ip address 10.1.5.1 255.255.255.0
Switch(config-if)# ip summary-address rip 10.2.0.0 255.255.0.0
Switch(config-if)# no ip split-horizon
Switch(config-if)# exit
Switch(config)# router rip
Switch(config-router)# network 10.0.0.0
Switch(config-router)# neighbor 2.2.2.2 peer-group mygroup
Switch(config-router)# end
Configuring Split Horizon
Routers connected to broadcast-type IP networks and using distance-vector routing protocols normally
use the split-horizon mechanism to reduce the possibility of routing loops. Split horizon blocks
information about routes from being advertised by a router on any interface from which that information
originated. This feature can optimize communication among multiple routers, especially when links are
broken.
Note In general, we do not recommend disabling split horizon unless you are certain that your application
requires it to properly advertise routes.
Beginning in privileged EXEC mode, follow these steps to disable split horizon on the interface:
Step 7 show ip interface interface-id Verify your entries.
Step 8 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 interface interface-id Enter interface configuration mode, and specify the interface to
configure.
Step 3 ip address ip-address subnet-mask Configure the IP address and the IP subnet.
Step 4 no ip split-horizon Disable split horizon on the interface.
Step 5 end Return to privileged EXEC mode.