Hi all, I'm trying to understand the following failover and clustering architecturthe, but I can not understand why on the Main server side we have 3 physicals Tomcat aplications servers and 1 physical Apache Server indicating a direct connection wiht another Apache at the Frontend? I'm confused with the architecture. Can you maybe please help me understand the infrastructure shown in att pic? Which server performs load balancing and HA?

Best regards

Apache Frontal
  /        \\

Apache1 Apache2
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TOMCAT1 TOMCAT1
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TOMCAT2 TOMCAT2
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TOMCAT3 TOMCAT3