Brocade Communications Systems ICX 7250 Series Configuration Manual page 67

To enable forwarding of IP directed broadcasts, enter the ip directed-broadcast command in device configuration mode.
device # configure terminal
device(config)# ip directed-broadcast
Syntax: [no] ip directed-broadcast
Brocade software makes the forwarding decision based on the router'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 no ip directed-broadcast command in device configuration mode.
device # configure terminal
device(config)# no ip directed-broadcast
To enable directed broadcasts on an individual interface instead of globally for all interfaces, enter the ip directed-broadcast command at
the interface configuration level as shown in the following example.
device # configure terminal
device(config)# interface ethernet 1/1/1
device(config-if-1/1/1 # ip directed-broadcast
Disabling forwarding of IP source-routed packets
A source-routed packet specifies the exact router path for the packet. The packet specifies the path by listing the IP addresses of the
router interfaces through which the packet must pass on its way to the destination. The Layer 3 switch supports both types of IP source
routing:
• Strict source routing - Requires the packet to pass through only the listed routers. If the Layer 3 switch receives a strict source-
routed packet but cannot reach the next hop interface specified by the packet, the Layer 3 switch discards the packet and sends
an ICMP Source-Route-Failure message to the sender.
NOTE
The Layer 3 switch allows you to disable sending of the Source-Route-Failure messages.
• Loose source routing - Requires that the packet pass through all of the listed routers but also allows the packet to travel through
other routers, which are not listed in the packet.
The Layer 3 switch forwards both types of source-routed packets by default. To disable the feature, use either of the following methods.
You cannot enable or disable strict or loose source routing separately.
To disable forwarding of IP source-routed packets, enter the no ip source-route command.
device # configure terminal
device(config)# no ip source-route
Syntax: [no] ip source-route
To re-enable forwarding of source-routed packets, enter the ip source-route command.
device # configure terminal
device(config)# ip source-route
Enabling support for zero-based IP subnet broadcasts
By default, the Layer 3 switch treats IP packets with all ones in the host portion of the address as IP broadcast packets. For example, the
Layer 3 switch treats IP packets with 10.157.22.255/24 as the destination IP address as IP broadcast packets and forwards the
packets to all IP hosts within the 10.157.22.x subnet (except the host that sent the broadcast packet to the Layer 3 switch).
Brocade FastIron Layer 3 Routing Configuration Guide
53-1003903-04
Configuring IP parameters - Layer 3 switches
67