Expand nginx server using Haproxy

Hello

I am using a server with nginx and php-fpm and Mariadb using xcache and memcache

Now i am thinking to get a second server and use it as web server using again the same setup nginx and php-fpm and Mariadb using xcache and memcache...

Now i want to ask where i must install Haproxy and how it will work with existing data or the new data that users will upload how they will go on both servers so when Haproxy share requests on both servers to be able to respond?

Is there any tutorial for this?

On Google i found a few but i can't get how i will configure it so both servers will have same data ....

Thank you

 

Ok, first of all you need, rsync+inotify to clone files to both servers, bi-directional or you may use lsyncd, it just does what you need, watch a directory and clone it when something is uploaded or deleted.

http://code.google.com/p/lsyncd/

Now for the haproxy part, its fairly easy to setup a loadbalancer,

global
#stats socket /var/run/haproxy.stat mode 666
        maxconn     8000
                daemon
nbproc 8
                defaults
                        mode        http
                        option    httplog
                        option    dontlognull
                                cookie      SERVERID insert nocache indirect
                                        clitimeout  60000
                                                srvtimeout  30000
                                                        contimeout  8000
                                                                option      httpclose
                                                                option      forwardfor
                                                                option redispatch

                                                                        maxconn     8000

                                                                        listen  http_proxy  loadbalancer_ip:82
                                                                                stats enable
stats scope    .
mode http
balance     roundrobin
cookie whoopi_server1 insert indirect
                                                                                                option      httpchk HEAD /index.php HTTP/1.1\r\nHost:\ domain.com
                                                                                                option      httpclose
                                                                                                        option      forwardfor
                                                                                                                server      server1 first_server_nginx:81 weight 1 maxconn 1500 cookie SERVER1 check

                                server      server2 second_server_nginx:81 weight 1 maxconn 2500 cookie SERVER2 check

Code (markup):

An example haproxy.cfg for you to load balance your webservers. Notice the timeout values if you lower them you may get lots of 503 errors from haproxy, depending on your backend`s response.

And, you asked where to install haproxy, of course you need to install it on the most reliable (Uptime performance) server you have. You could install haproxy on the same server within one of your webservers, for example, you may install haproxy on ip:82 and ip:81 would have nginx on same server(Both ips are same), you can do this by pre-routing port 80 responses to 82 with iptables where haproxy will listen for incoming connections.

Ok there is one question though, will you use some kind of replication between your database servers or one database server will serve the requests ?