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Catalyst 3560 Switch Software Configuration Guide
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Chapter 36 Configuring IP Unicast Routing
Configuring RIP
To restore clear text authentication, use the no ip rip authentication mode interface configuration
command. To prevent authentication, use the no ip rip authentication key-chain interface
configuration command.
Configuring Summary Addresses and 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 usually optimizes communication among multiple routers, especially when links
are broken.
Note In general, disabling split horizon is not recommended unless you are certain that your application
requires it to properly advertise routes.
If you want to configure an interface running RIP to advertise a summarized local IP address pool on a
network access server for dial-up clients, use the ip summary-address rip interface configuration
command.
Note If split horizon is enabled, neither autosummary nor interface IP summary addresses are advertised.
Beginning in privileged EXEC mode, follow these steps to set an interface to advertise a summarized
local IP address and to disable split horizon on the interface:
Step 3 ip rip authentication key-chain name-of-chain Enable RIP authentication.
Step 4 ip rip authentication mode [text | md5}Configure the interface to use plain text authentication (the
default) or MD5 digest authentication.
Step 5 end Return to privileged EXEC mode.
Step 6 show running-config interface [interface-id]Verify your entries.
Step 7 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 Layer 3
interface to configure.
Step 3 ip address ip-address subnet-mask Configure the IP address and IP subnet.
Step 4 ip summary-address rip ip address ip-network mask Configure the IP address to be summarized and the IP
network mask.
Step 5 no ip split horizon Disable split horizon on the interface.
Step 6 end Return to privileged EXEC mode.
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.