UDP load balancing on HAProxy Enterprise

You can load balance UDP (User Datagram Protocol) by using the HAProxy Enterprise UDP module.

What is UDP? Jump to heading #

Applications employ UDP when they need a fire-and-forget transport of messages over a network, with minimal overhead. Because UDP lacks the message delivery guarantees that TCP has, it can be ideal for some situations but not others. For example, when sending syslog messages over a network, you might prefer TCP if you require delivery of all messages. Or you might choose UDP if it’s acceptable to lose some messages, but allow the sender to continue sending messages without waiting for confirmation they’ve been received. Under some network conditions, such as where there’s significant packet loss, UDP can have better throughput. But it can perform worse in congested networks, since it lacks TCP’s congestion control.

How does the UDP module work? Jump to heading #

The UDP module adds support for a new section in your load balancer configuration called udp-lb. The udp-lb section defines the IP address and UDP port at which to accept datagrams. Also in this section, you’ll define the backend servers to load balance datagrams across. The module supports health checking servers and logging traffic too.