Huawei Quidway S3900 Series User Manual

Operation Manual – UDP-Helper
Quidway S3900 Series Ethernet Switches
Chapter 1
UDP-Helper Configuration
Huawei Technologies Proprietary
1-1
Chapter 1 UDP-Helper Configuration
1.1 Introduction to UDP-Helper
UDP-Helper is designed to relay specified broadcast UDP packets. It enables a device
to operate as a UDP packet relay. That is, it can convert broadcast UDP packets into
unicast packets and forward them to a specified server.
Normally, all the received broadcast UDP packets are passed to the UDP module. With
the UDP-Helper function enabled, the device checks the destination port numbers of
the received broadcast UDP packets and duplicates those with their destination port
numbers being that configured for UDP-Helper to the UDP-Helper module. The
UDP-helper module in turn modifies the destination IP addresses of the packets and
then sends the packet to the specified destination server.
 Note:
The DHCP Relay module uses UDP port 67 and 68 to relay BOOTP/DHCP broadcast
packets, so do not use port 67 and 68 as UDP-Helper relay ports.
With UDP-Helper enabled, the device relays the broadcast UDP packets whose
destination ports are one of the six UDP ports list in
Table 1-1 by default.
Table 1-1 List of default UDP ports
Protocol UDP port number
Domain name system (DNS) 53
NetBIOS datagram service (NetBIOS-DS) 138
NetBIOS name service (NetBIOS-NS) 137
TACACS (terminal access controller access control
system)
49
Trivial file transfer protocol (TFTP) 69
Time service 37

Huawei Quidway S3900 Series Specifications

General

Brand	Huawei
Model	Quidway S3900 Series
Category	Switch
Language	English