How about if you just use really large weight on the main servers, and really low on the fall back along with balance leastconn.
From: Karl Pietri [mailto:[email protected]] Sent: Friday, February 20, 2009 5:24 PM To: [email protected] Subject: priority servers in an instance Hello everyone, I am using haproxy with ruby on rails backend servers and am trying to setup a system that will have a few mongrels dedicated to priority traffic and spill over to the main pool if those are busy. i've attached a diagram of what i'm trying to accomplish. Eseentially i have 2 pools. all the servers in each pool have maxconn 1 (because mongrel sucks). a magorit of servers are in pool A and serve my normal traffic. I want to dedicate a few servers to pool B so that they are usually unloaded for some priority traffic. For the trafic going to that pool i want it to go to the few servers there unless they are all busy and in that case send the traffic to pool A for processing along with the rest of the stuff. I thought backup would do this but backup servers are only given traffic if all servers in the pool are down. not if all servers are busy. -Karl Pietri
