The difference between ratio session and ratio member.

Hello,

In fact, it's not easy to understand. if you do not use it regularly

• Ration (session) LB is usually used for protocols that transmit multiple messages over the same connection. When you use the Ratio (session) method, the system selects the pool memeber according the ratio that you set:

node 1 - ratio session 2

node 2 - ratio session 4

node 3 - ratio session 8 <- select this one

But in this case you must take into account the following elements (session is considered to be a transaction), example for radius or other, if 2 transaction occur trough the same session we will count 2 hits and not 1 even if it's the same session.

So, suppose that we have 3 transaction trough the same session you will have this lb:

• node 3 (1 transaction - session 1) -> ratio 8
• node 3 (2 transaction - session 1) -> ratio 8
• node 2 (3 transaction - session 1) -> ratio 4

...

Ration (member) is usually used when the server capacity of the pool members is different, and you want the system to weight connections to each pool member based on the value of the ratio weight you define:

Server 1: 2 cpu - 8g ram

Server 2: 1 cpu - 4g ram

So you will set your ration like that:

Server 1: ratio 8 (pool memeber 1.1.1.1:443)

Server 2: ratio 4 (pool memeber 1.1.1.2:443)

An in this case the lb is done based on the number of connection.

Regards