FortiOS server load balancing includes the features you would expect of any server load balancing solution. Traffic can be distributed across multiple backend servers based on multiple methods including static (failover), round robin, weighted to account for different sized servers, or based on the health and performance of the server including round trip time, number of connections. The load balancer supports HTTP, HTTPS, IMAPS, POP3S, SMTPS, SSL or generic TCP/UDP or IP protocols. Session persistence is supported based on the SSL session ID or based on an injected HTTP cookie.
Before you begin
Before you begin to configure load balancing from the web-based manager you should go to System > Feature Select and turn on Load Balancing. Its in the Additional Features list.
Also, if you set the Inspection mode to Flow-based in the System Information dashboard widget, you can only configure Virtual Servers with Type set to HTTP, TCP, UDP, or IP.
How this chapter is organized
This document contains detailed information about how to configure FortiOS server load balancing to load balance various types of traffic to multiple backend servers. This document describes all server load balancing configuration options and contains detailed configuration examples.
This FortiOS Handbook chapter contains the following sections:
Inside FortiOS: Server Load Balancing highlights the features and benefits of FortiOS server load balancing.
Basic load balancing configuration example introduces FortiOS server load balancing by providing a basic configuration example.
Configuring load balancing describes how to configure FortiOS server load balancing.
HTTP and HTTPS load balancing, multiplexing, and persistence describes FortiOS server load balancing features that support load balancing HTTP and HTTPS sessions.
SSL/TLS load balancingdescribes FortiOS server load balancing features that support load balancing SSL and TLS sessions.
IP, TCP, and UDP load balancing describes FortiOS server load balancing features that support load balancing IP, TCP, and UDP sessions.
The following configuration examples are also included:
- Example HTTP load balancing to three real web servers
- Example Basic IP load balancing configuration
- Example Adding a server load balance port forwarding virtual IP
- Example Weighted load balancing configuration
- Example HTTP and HTTPS persistence configuration