24-Port Layer 3 Switch Management Guide

IP R OUTING C OMMANDS
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ip split-horizon
Use this command to enable 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)#