Vagrant VMs that demonstrate HAProxy's load-balancing/session-persistence

Requirements: Vagrant, Virtualbox

Within the directory you clone the repo, command vagrant to initialize the 3 virtual machines with: vagrant up --provision

After instantiating, you may open your favorite browser and verify that both webservers are running by visiting http://localhost:8080/haproxy?stats. From there you can see information on both servers. You can visit each server within your private network by traveling to 172.16.0.2 and 172.16.0.3

Visit http://localhost:8081 and you should land yourself on either webserver's home page. If you refresh, you should still visit the same webserver. This demonstrates our HAProxy's session-persistence through cookies.

SSH into the other webserver with vagrant ssh webserver1, and simulate an outtage by typing: sudo service apache2 stop. You can go back to HAProxy's stats page and verify that your particular server has stopped. Upon refreshing http://localhost:8081, you will find yourself on your other, untouched webserver. This demonstrates HAProxy's load-balancing.

To resume a webserver, type sudo service apache2 start. You can verify that both servers are up and running on the HAProxy stats page, but the client with cookies will now only visit the remaining server thanks to session-persistence.

Halt the VMs with vagrant halt.

Links to helpful articles/demos: http://blog.haproxy.com/2012/03/29/load-balancing-affinity-persistence-sticky-sessions-what-you-need-to-know/