Design help for high TPS application

Hi Keith,

 

 

When the pool member goes down, does it continue to accept TCP connections? Does it send back HTTP 500's? Or does it stop answering TCP connection requests altogether?

 

 

What do you have the monitor interval and timeout set to? How long is it taking to mark a failing pool member down? How long do you want to have it take? You might be able to adjust the timeout to get better results.

 

 

Another option might be to detect a failure on a single connection in the LB_FAILED event (Click here). In theory, you should be able to select a new pool member and resubmit the request, but I haven't tested this myself and I've seen a few posts which indicate there are issues with this approach.

 

 

LB_FAILED event

 

http://devcentral.f5.com/Default.aspx?tabid=53&view=topic&postid=15238

 

 

LB_FAILED behavior, expected or not?

 

http://devcentral.f5.com/Default.aspx?tabid=53&forumid=5&tpage=1&view=topic&postid=15999

 

 

lb::reselect fails to select another node

 

http://devcentral.f5.com/Default.aspx?tabid=53&forumid=5&tpage=1&view=topic&postid=15864

 

 

How do I create a passive health monitor?

 

http://devcentral.f5.com/Default.aspx?tabid=53&forumid=5&tpage=1&view=topic&postid=1343313621

 

 

There is also a solution on AskF5 which describes an issue with LB::reselect. I haven't seen any additional info on the issue though.

 

 

The iRule LB::reselect command does not select the next pool member

 

https://support.f5.com/kb/en-us/solutions/public/8000/000/sol8033.html

 

 

Does anyone else have practical experience reselecting a pool member when one fails to respond? If so, did you use LB::reselect?

 

 

Aaron