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This document describes how to install HAProxy after the upgrade from 3.10.x to 4.0.x.
Author: Marc Cirauqui
Install HAProxy on the UI Server
Before you begin: check that you have the epel-release package installed. Otherwise HAProxy might not be available or it might be an old version.
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If you have multiple datacenters and are running websockify on each Remote Services server, you will need to define the backend for each server. Use Configure the UI server with the following model for the /etc/haproxy/haproxy.cfg file and make the changes described below.
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