Configure Directed Broadcast on a VLAN

Configure directed broadcast on a VLAN to enable or disable directed broadcast traffic forwarding for an IP interface.

Procedure

  1. In the navigation pane, expand Configuration > VLAN.
  2. Click VLANs.
  3. Select the Basic tab.
  4. Select a VLAN.
  5. Click IP.
  6. Click the Direct Broadcast tab.
  7. Select DirectBroadcastEnable.
    Important

    Important

    Configure multiple VLANs or IPs in the same subnet but in different systems simultaneously.

  8. Click Apply.

Direct Broadcast field descriptions

Use the data in the following table to use the Direct Broadcast tab.

Name

Description

DirectBroadcastEnable

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.

The default is disabled.
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