Dell POWEREDGE M1000E - Manual (Page 908)

38-16
Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
OL-13270-03
Chapter 38 Configuring IP Unicast Routing
Configuring IP Addressing
Use the no ip directed-broadcast interface configuration command to disable translation of directed
broadcasts to physical broadcasts. Use the no ip forward-protocol global configuration command to
remove a protocol or a port.
Forwarding UDP Broadcast Packets and Protocols
User Datagram Protocol (UDP) is an IP host-to-host layer protocol. UDP provides a connectionless
session between two end systems and does not acknowledge received datagrams. Network hosts can use
UDP broadcasts to find address, configuration, and name information. If such a host is on a network
segment that does not include a server, UDP broadcasts might not be forwarded. However, you can
configure an interface on a router to forward certain broadcast classes to a helper address. You can use
more than one helper address per interface.
You can specify a UDP destination port to control which UDP services are forwarded. You can specify
multiple UDP protocols. You can also specify the Network Disk Protocol (NDP), which is used by older
diskless Sun workstations and the network security protocol SDNS.
By default, both UDP and NDP forwarding are enabled if a helper address has been defined for an
interface. The description for the ip forward-protocol interface configuration command in the Cisco
IOS IP Command Reference, Volume 1 of 3: Addressing and Services, Release 12.2 lists the ports that
are forwarded by default if you do not specify any UDP ports.
If you do not specify any UDP ports when you configure the forwarding of UDP broadcasts, you are
configuring the router to act as a BOOTP forwarding agent. BOOTP packets carry DHCP information.
Step 3 ip directed-broadcast [access-list-number] Enable directed broadcast-to-physical broadcast translation on the
interface. You can include an ACL to control which broadcasts are
forwarded. When an access list, only IP packets permitted by the
access list can be translated
Note The ip directed-broadcast interface configuration command
can be configured on a VPN routing/forwarding(VRF)
interface and is VRF-aware. Directed broadcast traffic is
routed only within the VRF.
Step 4 exit Return to global configuration mode.
Step 5 ip forward-protocol {udp [port] | nd | sdns} Specify the protocols and ports the router uses when forwarding
broadcast packets.
• udp—Forward UPD datagrams.
port: (Optional) Destination port that controls which UDP
services are forwarded.
• nd—Forward Network Disk datagrams.
• sdns—Forward Secure Data Network Service (SDNS)
datagrams
Step 6 end Return to privileged EXEC mode.
Step 7 show ip interface [interface-id]
or
show running-config
Verify the configuration on the interface or all interfaces.
Step 8 copy running-config startup-config (Optional) Save your entries in the configuration file.
Command Purpose