ip subnet-zero

To enable the use of subnet zero for interface addresses and routing updates, use the ip subnet-zero global configuration command. To restore the default, use the no form of this command.
ip subnet-zero
no ip subnet-zero

Syntax Description

This command has no arguments or keywords.

Default

Disabled

Command Mode

Global configuration

Usage Guidelines

This command first appeared in Cisco IOS Release 10.0.
The ip subnet-zero command provides the ability to configure and route to subnet-zero subnets.
Subnetting with a subnet address of zero is discouraged because of the confusion inherent in having a network and a subnet with indistinguishable addresses.

Example

In the following example, subnet-zero is enabled:
 ip subnet-zero