The difference between ratio algorithm and dynamic ratio will be the same that is discussed in below post. Static type will be defined by administrator and Dynamic one will be processed by F5 with the help of Real time performance of server.
Now coming to, ratio (member) and ratio (node) algorithms and ratio (session).
Ratio (Member) – In this type, you assign ratio weight to each pool member according to capacity of server. The number of requests that each server receives over time will be directly proportional to assigned ratio. This type of configuration will be applicable to specific pool.
Ratio (Node) – In this type, you assign ratio to each node. So number of request that each node receives will be directly proportional to the assigned ratio to the node. When you configure ratio on node, that ratio will be applicable for all the pools where such node is added. In other words, wherever (any pool) you will add such node, the assigned ratio will be applicable to all such pools.
Major difference between both of above types is 1st type will be applicable to only that specific pool as you’re defining ratio under pool. And in 2nd, it will be applicable to all such pool where that particular node is available as you’re defining ratio under node itself.
Ratio (Session) – In this type, you assign weight to each pool member. F5 selects pool members according to the ratio of number of active sessions on each pool member. F5 considers all pending session as active session.
Hope it helps!
Below are configuration examples.
2. Ratio (Node) - Here while creating node, you need to define ratio to the node. Default assigned value is 1.
Once you define ratio to the node. You can call those node under pool. If under pool, Ratio (Node) algorithm is configured, then F5 will distribute requests according to weight configured on node level.
3. Ratio (Session) - This requires L4 and L7 profiles. F5 monitor pending and active sessions. And then calculates the weight.
Hope it helps!