Switch User Manual

ip split-horizon
This command enables split-horizon or poison-reverse (a variation) on an interface.
Use the
no form to disable split-horizon.
Syntax
ip split-horizon [ poison-reverse ]
no ip split-horizon
poison-reverse - Enables poison-reverse on the current interface.
Command Mode
Interface Configuration (VLAN)
Default Setting
split-horizon
Command Usage
• Split horizon never propagates routes back to an interface from which they
have been acquired.
• Poison reverse propagates routes back to an interface port from which they
have been acquired, but sets the distance-vector metrics to infinity. (This
provides faster convergence.)
Example
This example propagates routes back to the source using poison-reverse.
Console(config)#interface vlan 1
Console(config-if)#ip split-horizon poison-reverse
Console(config-if)#
ip rip authentication key
This command enables authentication for RIPv2 packets and specifies the key that
must be used on an interface. Use the
no form to prevent authentication.
Syntax
ip rip authentication key key-string
no ip rip authentication
key-string - A password used for authentication.
(Range: 1-16 characters, case sensitive)
Command Mode
Interface Configuration (VLAN)
Default Setting
No authentication
Command Usage
• This command can be used to restrict the interfaces that can exchange RIPv2
routing information. (Note that this command does not apply to RIPv1.)
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IP Routing Commands
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