HP 6125XLG R2306-HP 6125XLG Blade Switch Layer 3 - IP Services Command Referen - Page 145

Field protocol inpcb flags inpcb vflag Description Number of the protocol using the socket. Flags in the Internet PCB. IP version flags in the Internet PCB. 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. 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. Examples # Enable VLAN-interface 2 to receive and forward directed broadcast packets destined for the directly connected network. system-view [Sysname] interface vlan-interface 2 [Sysname-Vlan-interface2] ip forward-broadcast ip icmp fragment discarding Use ip icmp fragment discarding to disable forwarding of ICMP fragments. 137