14-2
To do…
Use the command…
Remarks
Specify the UDP destination port
number with which broadcast
packets are forwarded by UDP
Helper
udp-helper port
{
port-number
|
dns
|
netbios-ds
|
netbios-ns
|
tacacs
|
tftp
|
time
}
Required
No UDP port number is
specified by default.
Enter interface view
interface interface-type
interface-number
—
Specify the destination server to
which packets are to be forwarded
udp-helper server
ip-address
Required
No destination server is
specified by default.
z
The UDP Helper enabled device cannot forward DHCP broadcast packets. Thus, the UDP port
number cannot be set to 67 or 68.
z
You can specify a port number or the corresponding parameter for an UDP port to forward
packets. For example,
udp-helper port
53 and
udp-helper port
dns
specify the same UDP port
number.
z
The configuration of all UDP ports is removed if you disable UDP Helper.
z
You can configure up to 256 UDP port numbers to enable the forwarding of packets with these
UDP port numbers.
z
You can specify up to 20 destination servers on an interface.
Displaying and Maintaining UDP Helper
To do…
Use the command…
Remarks
Displays the information of packets
forwarded by UDP Helper
display udp-helper server
[
interface
interface-type
interface-number
]
Available in any view
Clear statistics about packets
forwarded by UDP Helper
reset udp-helper packet
Available in user view