a2billing on amazon

1. create two suitable machines on amazon ec2, Reserved Instances for 1 year 2. install and configure a2billing on both machine 3. synchronize (one way) machine one to machine two periodically. (i need to know how to change the frequency) 4. ensure that all the information and changes of settings on machine one are synchronized to machine two, including all data, settings and changes on both a2billing and FreePBX. 5. ensure that if machine one fail, we can switch to machine two immediately. (This can be manually switch.) Please let me know how to make the switch in detail. 6. setup periodically automatically backs to s3. Weekly and daily. And please let me know how to restore. 7. setup external monitoring using nagios+centreon on micro instance (make sure this is cheap one. less than $8 per month, otherwise we will install that on our own vps. ), will check disk,cpu load etc and inform if any problem. Conversation on msn are attached as reference. $550 in total. $250 milestone after software is installed. $250 milestone after software is configured. $50 milestone after nagios+centreon is setup. Milestones will be released after a quick test of the system.