Using URL parameters for load balancing with HAProxy
Solution 1:
A response was provided here on the haproxy mailing list
excerptsimply update the line below in your configuration to:
stick on url_param(SIMULATE_STICKY_SESSION,;) table simulateBy default, url_param search for a parameter after the question mark (?). The configuration above overwrite this by looking for your cookie from the semi-colon (;).
Note: you must be running a recent 1.5dev haproxy, preferably the dev 18.