I may have replied to one of your previous posts. If not consider reading the following.
I have used AWS and EC2 in the past and I believe Ian has also. We have talked about this on/off for about a year now.
I recommend against AWS unless you have no other choice.
Consider the Following
We have stopped using Amazon for anything except backups using s3cmd to safely backup critical folders to S3. (Moodle only)
One thing I have learned about Moodle is it extremely dependent on I/O due to database reads/writes. (not ideal on AWS)
Secondly, these pay by hour cloud providers may work but really aren't worth the headache and investment (look at Ian's efforts thus far and mine)...
Medium 30 x 24 = 720hr @ $130.00 (3.75GB Ram / 2EC 1 Core)
Large 30x24 = 720hr @ $260 (7.5GB Ram / 4EC 2 Core)
Based on my experience the price is high and performance average at best.
Unfortunately Moodle and AWS simply don't match up.
Anyone with a budget under $20/month
Find a dedicated VPS if your lucky and use nginx and caching
Anyone with a budget of $20 - $50/month
Find a dedicated VPS with higher specs or entry level dedicated server.
Anyone with a budget of 50+/month find a dedicated server on special. You will be the only one using the server, meaning no one else is using resources. This is a common issue in cloud/vps environments fighting for I/O and other resources.
Anyone with a budget of 100+/month do not rent a server, buy one!
You can typically find colocation hosting in USA data centers for 50+ and up per month. A decent spec. rented server might run $200-$300 monthly. Typically you can build and run the same spec. server for about half that cost. Which is what we do now!
[send me a private message] I may know a good co-lo in Europe.
Plus when you build it, you can tailor your server to your needs. I am hinting at I/O and ram.
Server Example: ($1750)
i5-2400 (4C @ 3.4Ghz) / 32GB RAM DDR3 1333 / 4 x SAMSUNG 830 128GB SSD / Adaptec RAID 6405 with 512Mb Cache (Raid 10)
Colocation Example ($711 / year)
100mbps / 10 IP / Power / Control Panel
I consider the above a budget server yet extremely powerful. I dare you to configure something on Dell's website that comes close. In Raid10 with the adaptec raid card this server will be able to handle extreme I/O of Moodle's read/writes requirements.
Total cost about $2500 for the first year which puts us around $200 monthly or less then the Large EC2 instance with 7.5GB of ram and 4EC. Plus we own the server and expect to keep it in production for 2-3 years. Also in the future we may turn this into a dedicated MySQL server depending on how everything plays out.
If your using Moodle, why bother with AWS?