Web hosting just got more interesting
Posted 2008-03-27 01:52 PMAmazon EC2 and S3 are perhaps the most recognizable offerings in the so called cloud computing space. The EC2 service offers a utility pricing model for a slice of a dedicated server. Each EC2 instance is a Xen based Virtual Private Server (VPS) with several options for server space and RAM.
Of course EC2 has become an interesting option for people in need of cheap dedicated hosting space for whatever needs. EC2 has been particularly useful for the option of starting up any number of servers within minutes and dismissing them at any time. If a customer starts an EC2 instance for one hour, the bill is ten cents. This is true utility hosting.
Unfortunately there have been a number of deal breakers for using EC2 as a general hosting option. Probably the most common complaints have been over a lack of persistent storage (data vanishes if the instance dies,) no option for geographic redundancy (no method of ensuring that two different instances could run in different data centers) and the lack of a dedicated IP address (IP is reallocated randomly when instance dies.)
Of these problems there was really only one major road block for most people. The lack redundant storage could be dealt with by using creative strategies to squirrel the data to S3. Though geographic redundancy is nice, not everyone employs such precautions because doing so runs up the hosting bill. The one major problem that there was no real easy way to get around was the lack of static IP addressing.
A dedicated IP address is extremely important for hosting. DNS servers need an IP address to associate with your domain. Previously only a DNS solution typically used for home based dynamic IP addressing could be used to get around this problem. Secure certificates which are used for running things like shopping carts and secure logins also need to be associated with a static IP address. These are the major reasons but the list goes on.
Now, Amazon has squashed some of these problems. New instances can now be started in a number of (I see three options right now) availability zones which are insulated from each other. That means a data center failure in one zone won’t affect an instance in another zone. This feature could be used as a solution to the problem of geographic redundancy. At this point I am not sure where these zones are located but I believe at least one of them is in Europe.
The other new feature which is the most exciting to me is the Elastic IP address offering. An IP address can be allocated to your account until you explicitly release it and it appears that you can have as many addresses as you like. The IP address can be associated with any instance or to none at all. IP addresses which are allocated to an instance are free but those which are not allocated are billed at one cent per hour which works out to $7.20 per month.
Unfortunately there is one big caveat to the new IP addresses. From what I can see, an instance can only be allocated one IP address at a time. This still gives EC2 users all the benefits mentioned above, but webmasters will have to setup each site with a secure certificate on a separate instance (and running another $72 per month for the instance.) There are work-arounds to this problem, but I am not sure that any of them are in wide enough usage to be trusted at this time.
Overall, these new additions bring down some walls for a lot of people and makes Amazon web services a much more solid option. These features have been often requested from day one, thank you Amazon for finally coming through.
Read the announcement from Amazon.
