Forum Discussion

Steven_J__Willi's avatar
Steven_J__Willi
Icon for Nimbostratus rankNimbostratus
Apr 27, 2014

Priority Group Activation, why use it?

If you have 3 members that are active within a pool and you select round robin LB method and set the priority group activation for less than 2, the virtual server is only going to use two of three no...
application delivery
LTM
management
performance
Steven_J__Willi's avatar
Steven_J__Willi
Icon for Nimbostratus rankNimbostratus
Apr 27, 2014

 

So the question is"assuming all pool members are available, using the configuration in the diagram, how many of the next of the next 100 requests will members 172.16.20.1, .2, .3 receive?

 

The answer is .2 and .3 will get 50 each. So I get that round robin will evenly distribute, but why in the world would you ever configure this? If you configured the PGA to less than 1 would it only use .2 for traffic requests? If you changed the 2 to 3 would it then use all three members?

 

I am just trying to understand a real world scenario with this PGA stuff...if all members in a pool are active, they should all be used in my opinion.

 

Also this is not an "answer" but "add comment" wont let me post a image.

 

  • nathe's avatar
    nathe
    Icon for Cirrocumulus rankCirrocumulus
    Apr 27, 2014
    Steven. Real world example I've seen. 4 pool members, 2 in DC1 and 2 in the DC2. Normal traffic is everything goes to the pool members in DC1 but if these pool members go down then use pool members from DC2 as a backup.