Ratio (Session) and Least Sessions

Hi Ahmadmhd,

The Ratio (member) method can be used to load balance most connection types. When you configure the Ratio (member) load balancing method you should assign a ratio weight to each pool member that is proportional to the capacity of the server.

Ratio:-

The ratio method is appropriate to use if same pool members are more powerful than others. In this example, the ratio is set as 3:2:1:1.

As a result, BIG-IP sends three times as many requests to server 1 and twice as many requests to server 2 (as compared with servers 3 & 4)

If one server that was much faster than the others. After receiving the available load balancing methods to choose Ratio method. Knowing it would allow BIG-IP to letter utilize his more efficient server.

As request are processed, all available members are given one client request.

Then three or greater, and so on until the member with the highest ratio has been given the number of requests equally its ratio. Then the whole process starts over again.

Remember that both ratio and Round robin are static load balancing methods. This means that if a server with a higher ratio is available, it will still receive more requests then the other servers even if its performance is shown then the others.

If you want to consider server performance, you should use one of the dynamic load balancing methods.

Least Connections :- 

The least connections load balancing method uses the current connection to decide where to send the next client request. Assuming the current connection counts are listed.

The next connection will go to server1. now server1 & 2 have equal counts so BIG-IP will round robin between them.

Assuming connections count stay as shown, now server 1,2 &3 all have equal counts so BIG-IP will round robin between all three.

Least connections is appropriate for many cases but may be most relevant when the client connection length varies significantly and round robin could result in uneven loads.    

HTH

F5 Design Engineer

🙏