https://aws.amazon.com/solutions/limit-monitor/
It starts having issues when you get to 5,000+ ec2 instances, but it's somewhat understandable that they don't aim to support that level of usage within a single AWS account.
On another bullet point: if you go serverless (API/HTTP Gateway, Lambda, Dynamo DB), you automatically get full region DR. I personally recommend HTTP Gateway if you can swing it, API gateway is only worth of it you are doing personal projects (mostly free tier) or are seriously leveraging the API gateway specific features
It only notifies you about your own Service Limits, so you will know before you hit one in an unfortunate moment. It's important to monitor that, but it doesn't protect or notify you against cloud provider's own limitations. A scale-out event can still fail if AWS has no more extra capacity ("full") even if your limits allow you otherwise.
AFAIK there's currently no way to know it beforehand if they actually have the capacity or not.
But then don’t hire a bunch of old school net ops folks who got one certification and call themselves consultants when all they know how to do are lift and shifts.
Literally everywhere I go, and it's a lot of different organisations, there's people at every level and every job title unconditionally stating that the cloud is "cheaper".
They look at a cloud VM tier that is literally 3x more expensive per year than their current hardware and say that it is "cheaper" with a straight face.
They look at a SaaS that costs $1M per year while they're currently "burning" $200K in staffing costs to maintain an equivalent on-prem and say that they have to move to the cloud to save money.
They run VMs 24/7 with zero users and say that this is efficiency.
Nobody I've seen uses reserved instances or any similar cost-cutting measure, such as spot instances.
For fuck's sake, I just worked on a project to move users from one cloud service that cost $30/user/month to another cloud service that costs $100/user/month supposedly to... wait for... "save money".
But then don’t hire a bunch of old school net ops folks who got one certification and call themselves consultants when all they know how to do are lift and shifts.
Then you're very misinformed.
As a cloud administrator, I see resource availability and account limits on a weekly basis going back years.
I tell people:
- to pre-provision at least some extra servers rather than wait for an autoscaling operation to fail.
- that new instance types often are rolled out gradually, and lead time is often 1 month in AWS
- that killing a 1000-node cluster then expecting to immediately rebuild it often doesn't work.
- for DR and BCP planning, each region (or AZ) should be able to handle enough load at all times in case one region (or AZ) is unavailable. I've never seen anybody do that, even after I told them, because cost.