This article focuses on how to configure Load Balancing to enable traffic to be sent and received by one interface connection during one session.
When applying Load Balancing you may choose one of four options: Basic Failover, Round Robin, Spill-over, and Ratio.
It has been reported that when enabling Round Robin functionality there might occur connectivity issues related to the appliance switching/distributing the traffic and sessions between the available interfaces. Basically the session started on one interface will be interrupted when Round Robin switches to another WAN interface resulting in session time-outs.
The suggested workaround is to enable Ratio functionality and tick the option:
"Use Source and Destination IP Address binding"
Additionally, in the Ratio setup you will have to choose the percentage of traffic dedicated to an interface. To obtain similar outcome as in Round Robin please set the same percentage for all interfaces.