Forum Discussion

HG's avatar
HG
Icon for Cirrus rankCirrus
Nov 13, 2015

LTM - Least Connections loadbalancing method

Hello,

 

Lets assume that we have 2 pools with different name having both the same 2 members. On both pools least connections load balancing method have been chosen based on member. By using irules we specify which pool is gonna be chosen based on the [HTTP::host] content. My question is how the F5 LTM will handle these requests ? Would it be the same to have just one pool with those 2 members ??? In other words by using 2 pools the F5 runs 2 instances for the least connection LB method (member) or it counts the connections in total ? Based on the same scenario in case we use least connection LB method (NODE) do we expect the same behaviour ??

 

Thanks

 

  • Ok so in general it makes sense to use 2 pools with the same members (X,Y on both) and the least connections (member) load balancing method because the connections are counted on each pool separately although the same node is part of both pools.

     

  • If you select Least Connections (Member) as the balancing method, the balancing decision will be based on the connection counters of a particular Pool. You can call this isolated balancing, because the connection counters outside the context of a particular Pool do not matter.

     

    If you change the balancing method to Least Connections (Node), the connection counters outside the context of a given pool will start to matter.

     

    It sounds bulky, but hope it will make sense.