The Fortinet server load balancing includes the features for any server load balancing solution. It intercepts incoming traffic with a virtual server and shares it among backend real servers. By doing this, the Fortinet unit enables multiple real servers to respond as if they were a single device or virtual server.
The network traffic is distributed across multiple backend servers based on 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.
Working of Fortinet Load Balancer
ü There can be 8 real servers connected to one virtual server.
ü The server topology is transparent to end users, and the users interact with the system as if it were only a single server with the IP address and port number of the virtual server.
ü The real servers may be interconnected by high-speed LAN or by geographically dispersed WAN. This schedules requests to the servers to makes parallel services of the virtual server.
A virtual server includes a virtual server IP address bound to an interface. The virtual server IP address is the destination address incoming packets to be load balanced and the virtual server is bound to the interface that receives the packets to be load balanced. The traffic load is spread evenly across all servers. Sessions are not assigned as distribution of load can be changed depending on the servers working at that moment.
One of the servers is set in the standby mode and all other servers are active. For instance, if there are 3 servers, 2 of them will be in active mode and other one will be in standby mode. If one of the servers in active mode fails, the server in standby mode is changed to active mode and sessions are load balanced. If both servers in active mode fail, all sessions are sent to the real server in standby mode.