The elasticity, no capex and api management are great. But bending over backwards to deal with their terrible SAN, saturated layer 2 and low reliability easily wastes at least as much engineer time as it saves in ops. If the OP's 100 boxes are similar to most of the other AWS deployments I'm familiar with it's likely that'd be 10 or less actual machines to manage.
Don't get me wrong - the idea is great and it's great for really low end workloads where the gotchas don't matter or really big systems where you'd be managing against most of those issues anyway.
But in the middle of the two there is a dead space that I bet a lot of shops are stuck in - double digit instance numbers running a workload that a 2-4 servers could handle with plenty of leg room.
If you're deciding on a cloud provider in 2012 I think it makes a lot of sense to shop around. There are lots of people doing the on demand api deployment thing now with different trade offs. I like joyent a lot (local reliable io) or providers with cloud and a colo area even if it's exorbitant - as paying five hundred dollars a month for instnaces one ssd could replace sucks.
I second this. If you are in the position to commit either way I'd suggest to first run a simple benchmark with your app on EC2 versus some cheap dedicated server.
As parent says: EC2 does have its place, but for deployments in the 10-20 hosts range (or an app with "special needs") you tend to pay through the nose. Keep in mind that the amount that you pay for a fraction of a server on EC2 will rent you the entire box elsewhere.
Pretty much exactly this (I've posted this statement nearly word for word several times in response to articles like this). Basically EC2 or Rackspace Cloud, etc. are very good for small startups running a handful or two of instances, or really large companies that need hundreds/thousands of instances under which scenario hardware might very well be the more expensive option.
Don't get me wrong - the idea is great and it's great for really low end workloads where the gotchas don't matter or really big systems where you'd be managing against most of those issues anyway.
But in the middle of the two there is a dead space that I bet a lot of shops are stuck in - double digit instance numbers running a workload that a 2-4 servers could handle with plenty of leg room.
If you're deciding on a cloud provider in 2012 I think it makes a lot of sense to shop around. There are lots of people doing the on demand api deployment thing now with different trade offs. I like joyent a lot (local reliable io) or providers with cloud and a colo area even if it's exorbitant - as paying five hundred dollars a month for instnaces one ssd could replace sucks.