Hi, If cookie insert is not an option, then in 1.5-dev7, you can perform cookie persistence learning the application cookie and store it in a stick table. It's like appsession, unless it will survive a reload and you can share it between HAProxy boxes. :)
cheers On Mon, Oct 31, 2011 at 7:40 PM, Cyril Bonté <[email protected]> wrote: > Hi, > > Le Lundi 31 Octobre 2011 17:21:02 Piavlo a écrit : >> I have been using *capture cookie* and *appsession *in one haproxy >> configuration for sticky sessions. >> The problem is that then haproxy restarted/reload or domain is migrated >> to failover server the sticky data is lost. >> Today I realised that I don't need to use sticky sessions at all in >> haproxy - what I do is setup custom session name >> different in each backend http server based on it's name and then using >> acl match on *hdr_beg(Cookie)* to direct to the correct backend >> and if Cookie is not set then send it to round robin backend that has >> all the http servers listed. > > Is there any reason to use a different cookie name per server instead of using > much standard behaviour of haproxy (using cookie insert and others) ? > Your configuration would be a lot more simple and maintainable (see at the > end). > >> Below is the relevant frontend & backend config. >> It works great - but there is one problem. It's is very important that >> the *maxconn* that is set in *server *will be set globally per real http >> server >> but since I now have same server http server listed twice. >> For example for lb-srv1 web server there are *lb-srv1/lb-srv1* and >> *testing_rr/lb-srv1* - it means the total maxconn for lb-srv1 is now x2 >> larger. >> I could split split the maxconn between lb-srv1/lb-srv1 and >> testing_rr/lb-srv1 - so that in total it's 900 - but this will not use >> the possible 900 slots >> since there is no way to know that ratio of lb-srv1/lb-srv1 vs >> testing_rr/lb-srv1 and it's highly dynamic. >> >> Is there some trick to share the same *maxconn* for lb-srv1/lb-srv1 >> testing_rr/lb-srv1 >> Or something similar to*track* - that would make *server* track other >> *server*'s maxconn too? and not only health checks. > > No, or not yet. > >> afaiu the haproxy backends lb-srv1 & lb-srv1 cannot be load balanced >> but only chosen based on acl or as default fallback? > > No. > >> ------------------------------------------------------------ >> frontend testing 0.0.0.0:88 >> mode http >> maxconn 20000 >> >> option httplog >> monitor-uri /up.html >> >> option http-server-close >> option forwardfor >> reqadd X-Forwarded-Proto:\ http >> >> acl acl-lb-srv1 hdr_beg(Cookie) lb-srv1= >> acl acl-lb-srv1-up nbsrv(lb-srv1) 1 >> >> acl acl-lb-srv2 hdr_beg(Cookie) lb-srv2= >> acl acl-lb-srv2-up nbsrv(lb-srv2) 1 >> >> use_backend lb-srv1 if acl-lb-srv1 acl-lb-srv1-up >> use_backend lb-srv2 if acl-lb-srv2 acl-lb-srv2-up >> default_backend testing_rr >> >> monitor fail if !acl-lb-srv1-up !acl-lb-srv2-up >> >> backend lb-srv1 >> mode http >> option httpchk /up.html >> option abortonclose >> >> server lb-srv1 lb-srv1.private:82 maxconn 900 check >> inter 2000 fall 3 >> >> backend lb-srv2 >> mode http >> option httpchk /up.html >> option abortonclose >> >> server lb-srv2 lb-srv2.private:82 maxconn 900 check >> inter 2000 fall 3 >> >> backend testing_rr >> mode http >> option httpchk /up.html >> option abortonclose >> >> balance roundrobin >> server lb-srv1 lb-srv1.private:82 maxconn 900 track >> lb-srv1/lb-srv1 >> server lb-srv2 lb-srv2.private:82 maxconn 900 track >> lb-srv2/lb-srv2 >> ----------------------------------------------------------- > > Proposed version (untested) : > ------------------------------------------------------------ > listen testing 0.0.0.0:88 > mode http > maxconn 20000 > > option httplog > monitor-uri /up.html > > option abortonclose > option http-server-close > option forwardfor > reqadd X-Forwarded-Proto:\ http > > acl acl-lb-down nbsrv 0 > monitor fail if acl-lb-down > > cookie lb insert > server lb-srv1 lb-srv1.private:82 maxconn 900 cookie srv1 > check inter 2000 fall 3 > server lb-srv2 lb-srv2.private:82 maxconn 900 cookie srv2 > check inter 2000 fall 3 > ----------------------------------------------------------- > > -- > Cyril Bonté > >
