Region A failure

To simulate a failure of region A, we'll simply stop the web server, which is attached to the ELB as follows:

    [root@ip-172-30-0-153 ec2-user]# service nginx stop
    Stopping nginx:                                            [  OK  ]

After a short period, the web console will show that the health check for region A is failing:

Region A failing health check

Our North American user (left) now sees region B instead:

Left: Region B served to North American users due to failover. Right: Region B served to Australian users as normal.