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14
UDP Helper Configuration
This chapter includes these sections:
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Displaying and Maintaining UDP Helper
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UDP Helper Configuration Examples
Currently, only VLAN interfaces support UDP Helper related configuration.
Introduction to UDP Helper
A host may need to send broadcast packets to obtain network configuration information or request the
names of other devices on the network. However, if the server or the device to be requested is located
in another broadcast domain, the host cannot obtain such information through broadcasting.
To solve this problem, the device provides the UDP Helper function to relay specified UDP packets. In
other words, UDP Helper functions as a relay agent that converts broadcast packets into unicast
packets and forwards them to a specified destination server.
With UDP Helper enabled, the device decides whether to forward a received broadcast packet
according to the UDP destination port number of the packet.
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If the destination port number of the packet matches the one pre-configured on the device, the
device modifies the destination IP address in the IP header, and then sends the packet to the
specified destination server.
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If not, the device sends the packet to the upper layer protocol for processing.
Configuring UDP Helper
Follow these steps to configure UDP Helper:
To do…
Use the command…
Remarks
Enter system view
system-view
—
Enable UDP Helper
udp-helper enable
Required
Disabled by default.