IP Routing Features

Configuring IP Parameters for Routing Switches

 

Changing the TTL Threshold

 

The configuration of this parameter is covered in chapter 7, “Configuring IP

 

Addressing”.

 

Enabling Forwarding of Directed Broadcasts

 

A directed broadcast is an IP broadcast to all devices within a single directly-

 

attached network or sub-net. A net-directed broadcast goes to all devices on

 

a given network. A sub-net-directed broadcast goes to all devices within a

 

given sub-net.

 

 

N o t e

A less common type, the all-sub-nets broadcast, goes to all directly-attached

 

sub-nets. Forwarding for this broadcast type also is supported, but most

 

networks use IP multicasting instead of all-sub-net broadcasting.

 

Forwarding for all types of IP directed broadcasts is disabled by default. You

 

 

can enable forwarding for all types if needed. You cannot enable forwarding

 

for specific broadcast types.

 

To enable forwarding of IP directed broadcasts, enter the following CLI

 

command:

 

HPswitch(config)# ip directed-broadcast

 

Syntax: [no] ip directed-broadcast

 

HP software makes the forwarding decision based on the routing switch's

 

knowledge of the destination network prefix. Routers cannot determine that

 

a message is unicast or directed broadcast apart from the destination network

 

prefix. The decision to forward or not forward the message is by definition

 

only possible in the last hop router.

 

To disable the directed broadcasts, enter the following CLI command:

 

HPswitch(config)# no ip directed-broadcast

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