ip directed-broadcast (for a VLAN)

Configure the device to forward directed broadcasts for a VLAN.

Syntax

Command Parameters

enable

Specifies that an Isolated Routing Port (IRP) can forward directed broadcast traffic. A directed broadcast is a frame sent to the subnet broadcast address on a remote IP subnet. By disabling or suppressing directed broadcast on an interface, all frames sent to the subnet broadcast address for a local router interface are dropped. Disabling this function protects a host from possible denial of service (DoS) attacks.

With the feature enabled, the Control Processor (CP) does not receive a copy of the directed broadcast. As a result, the system does not respond to a subnet broadcast ping sent from a remote subnet.

Default

The default is disabled.

Command Mode

VLAN Interface Configuration