使用Nginx进行HTTP负载平衡

Question

I have a configuration like this.

upstream servers{
                server localhost:port1;
                server localhost:port2;
                server localhost:port3;

}

server{
       listen nginx_port;
       server_name localhost 

       location{
                proxy_pass http//:servers;
}



}

Now what I want to know is how to keep a user's session alive while maintaining (I mean temporarily closing) one server. Let say I have a 3 page registration now user is connected to localhost:port1 and working on page 2 in the meantime if I want to close the server(localhost:port1) and forward the user to next server(localhost:port2) keeping the session alive I mean the user should be able to complete his registration without any trouble then what i have to do in the nginx configuration file. is it possible?

Answer 1

You can't do this with nginx, as nginx is not what's providing the session functionality. You need to do this with your upstream servers by configuring them to use session storage that's sharable by all the servers (like a database or memcache) instead of server-specific session storage (like files in a temp dir on the local hard drive.) How you do that will vary based on whatever your upstream servers are. For example, if you're using Zend, you might implement a database save handler .

(I'm assuming here that your config is just an example and that you don't actually have three identical upstream servers on the same machine.)