HP MSR2000/3000/4000 Router Series Layer 3 - IP Services Command Reference

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ip forward-broadcast
Use ip forward-broadcast to enable an interface to receive and forward directed broadcast packets
destined for the directly connected network.
Use undo ip forward-broadcast to disable an interface from receiving and forwarding directed
broadcast packets destined for the directly connected network.
Syntax
ip forward-broadcast
undo ip forward-broadcast
Default
An interface cannot receive or forward directed broadcasts destined for the directly connected network.
Views
Interface view
Predefined user roles
network-admin
Usage guidelines
A directed broadcast packet is destined for all hosts on a specific network. In the destination IP address
of the directed broadcast, the network ID identifies the target network, and the host ID is made up of all
ones.
If an interface is allowed to forward directed broadcasts destined for the directly connected network,
hackers can exploit this vulnerability to attack the target network. In some scenarios, however, an
interface must receive and send such directed broadcast packets to support UDP helper and Wake on
LAN.
This command enables an interface to accept directed broadcast packets that are destined for and
received from the directly connected network to support UDP helper, which converts the directed
broadcasts to unicasts and forwards them to a specific server.
The command also enables the interface to forward directed broadcast packets that are destined for the
directly connected network and are received from another subnet to support Wake on LAN, which sends
the directed broadcasts to wake up the hosts on the target network.
Examples
# Enable the interface Ethernet 1/1 to receive and forward directed broadcast packets destined for the
directly connected network.
<Sysname> system-view
[Sysname] interface ethernet 1/1
[Sysname-Ethernet1/1] ip forward-broadcast
ip icmp error-interval
Use ip icmp error-interval to set the interval and bucket size for ICMP error messages.
Use undo ip icmp error-interval to restore the default.