Load balancing Kofax ControlSuite (Equitrac, AutoStore and Output Manager)

How to load balance Kofax ControlSuite

For a Kofax ControlSuite deployment, the preferred and default load balancer configuration uses Layer 4 DR Mode (Direct Routing, aka DSR / Direct Server Return) where possible. This is a very high performance solution that requires little change to your existing infrastructure.

The load balancer can be deployed in 4 fundamental ways: Layer 4 DR mode, Layer 4 NAT mode, Layer 4 SNAT mode and Layer 7 SNAT mode. However, we will only be using Layer 4 DR mode, Layer 4 NAT mode or Layer 7 SNAT modes in this guide. It is necessary to solve the ARP problem on the real print servers. This is a straightforward process and is detailed in the section “Configuring Print Servers for Load Balancing” which can be found in the deployment guide.

Layer 4 DR Mode
One-arm direct routing (DR) mode is a very high performance solution that requires little change to your existing infrastructure.

• DR mode works by changing the destination MAC address of the incoming packet to match the selected Real Server on the fly which is very fast
• When the packet reaches the Real Server it expects the Real Server to own the Virtual Services IP address (VIP). This means that you need to ensure that the Real Server (and the load balanced application) respond to both the Real Servers own IP address and the VIP
• The Real Server should not respond to ARP requests for the VIP. Only the load balancer should do this. Configuring the Real Servers in this way is referred to as Solving the ARP Problem. Please refer to the deployment guide for more information
• On average, DR mode is 8 times quicker than NAT for HTTP, 50 times quicker for Terminal Services and much,
  much faster for streaming media or FTP
• The load balancer must have an Interface in the same subnet as the Real Servers to ensure layer 2 connectivity required for DR mode to work
• The VIP can be brought up on the same subnet as the Real Servers, or on a different subnet provided that the load balancer has an interface in that subnet
• Port translation is not possible in DR mode i.e. having a different RIP port than the VIP port
• DR mode is transparent, i.e. the Real Server will see the source IP address of the client

For additional deployment methods please refer to the full deployment guide.