Specifying By Udp Port Number Which Udp Broadcasts Are Forwarded - 3Com 3C13636 Configuration Manual

3Com Router 3000 Ethernet Family
Configuration Guide

7.2.2 Specifying by UDP Port Number which UDP Broadcasts are forwarded

With UDP Helper enabled, the system by default unicasts the broadcast packets with
the UDP ports listed in the following table. You can configure up to 256 UDP ports with
UDP Helper.
Table 7-2 Default UDP ports
Trivial file transfer protocol (TFTP)
Domain name system (DNS)
Time service
NetBIOS name server (NetBIOS-NS)
NetBIOS datagram server (NetBIOS-DS)
Terminal access controller access control system (TACACS)
Perform the following configuration in system view.
Table 7-3 Configure/disable the system to forward the UDP broadcasts with the
specified UDP port number
Configure the system to forward the
UDP broadcasts with the specified UDP
port number
Disable the system to forward the UDP
broadcasts with the specified UDP port
number
Note that:
Before you can specify by UDP port number which UDP broadcasts are forwarded,
you must enable UDP Helper.
The dns, netbios-ds, netbios-ns, tacacs, tftp, and time keywords represents
the six default ports. When specifying a default port, DNS for example, you can
specify its port number 53 directly or specifying the keyword dns.
When
current-configuration command displays the default UDP port numbers only
when they are disabled to use UDP Helper.
Protocol
Operation
displaying the information
3Com Corporation
Chapter 7 UDP Helper Configuration
udp-helper
netbios-ds | netbios-ns | tacacs | tftp |
time }
undo udp-helper port { port | dns |
netbios-ds | netbios-ns | tacacs | tftp |
time }
about UDP
7-2
UDP port number
69
53
37
137
138
49
Command
port { port | dns |
helper, the display