ahah, you can call me Baptiste :) You miss a "stick on cookie(PHPSESSID)". Also consider using the same expire delay you have on your application server.
And last but not least, add a "peers" section (and a peer directive on the stick-table definition) where you provide all your HAProxy server IPs in order to get the table of each HAProxy synchronized. then you're done. Baptiste On 2/8/13, Alex Davies <[email protected]> wrote: > Hi Willy, > > Thanks for your suggestion. I'm guessing you mean something like this > backend: > > backend x > balance roundrobin > stick-table type string size 32k peers other_haproxy_server expire 24h > stick store-response set-cookie(PHPSESSID) > > If I understand you correctly, you are saying that this will only mean that > sessions become "persistant" once PHPSESSID is set. So, to translate into > practicality, as long as the login page creates the relevant cooke (and it > does not subsequently change once logged in), this should work nicely. > > Thanks, > > -Alex > > > > On Sun, Feb 3, 2013 at 7:59 AM, Baptiste <[email protected]> wrote: > >> Hi, >> >> the only way you could do what you want for now is using stick tables >> (and haproxy 1.5-dev17). >> You can learn the Set-Cookie from the server and match the Cookie in >> the table from the client. >> That way, all the request from a user will be sent to the same server, >> from the first to the last one. >> >> Today, haproxy is able to hash a HTTP header for load-balancing, so a >> configuration like: >> balance hdr(Cookie) >> could do the trick, but it means that ALL clients cookie to >> load-balance. And worste, since there is no phpsessionid cookie on the >> first request, there are chances that the first and the second >> requests won't be routed to the same server. >> >> I guess it would be possible soon to have a: >> balance cook(PHPSessionID) >> but it won't fix the sticking issue between first and second request >> since the cookie is not present in the first request. >> >> So if you really want using the algorithm method, you must be able to >> share cookies between your backend servers, only lucky people will be >> able to get authenticated. >> Well, maybe there are some dirty tricks like managing a farm for >> cookie-less clients and configuring PHP to learn an unknown session on >> the fly. >> >> Baptiste >> >> >> On Sun, Feb 3, 2013 at 2:03 AM, Alex Davies <[email protected]> wrote: >> > Hi All, >> > >> > What is the best way to configure haproxy to hash based on an >> > application >> > cookie (such as PHPSESSID), in a way that is consistent (meaning >> > multiple >> > haproxy servers will route to the same backend), ideally including the >> > ability to weight backends (the configuration would clearly have to be >> the >> > same on these different boxes). >> > >> > appsession obviously allows this for a single HAProxy server, but it >> seems >> > from the documentation that it generates a server based on the hash at >> the >> > start of each session, so if the same session hit a different but >> > identically configured haproxy server it would end up with a >> > >> > Thanks, >> > >> > -Alex >> >
