I was just playing around with the configuration from the excellent blog entry on e-commerce overload protection: http://blog.haproxy.com/2012/09/19/application-delivery-controller-and-ecommerce-websites/
If you have a PHPSession or ASPsessionID cookie then you can track the total number of users as follows: listen L7-Test bind 192.168.64.27:80 transparent mode http acl maxcapacity table_cnt ge 5000 acl knownuser hdr_sub(cookie) MYCOOK http-request deny if maxcapacity !knownuser stick-table type string len 32 size 10K expire 10m nopurge stick store-response set-cookie(MYCOOK) stick store-request cookie(MYCOOK) balance leastconn cookie SERVERID insert nocache server backup 127.0.0.1:9081 backup non-stick option http-keep-alive option forwardfor option redispatch option abortonclose maxconn 40000 server Test1 192.168.64.12:80 weight 100 cookie Test1 server Test2 192.168.64.13:80 weight 100 cookie Test2 But what if you only have a single source IP (so you still want to use cookies to track the usage AND stickyness) but the application doesn't have its own unique session id? Can you do something like using gpc0 to store a random haproxy session id (for overload) and yet still using cookie SERVERID for the persistence? Or using a big IP stick table even though all the IPs will be the same? Or am I just being really stupid today , which is not unusual :-). Thanks in advance. -- Regards, Malcolm Turnbull. Loadbalancer.org Ltd. Phone: +44 (0)330 1604540 http://www.loadbalancer.org/