AWS Running out of Capacity in an Availability Zone Near You!

Cloud is fantastic, but it’s not infinite as I discovered this week with Amazon Web Services..!

Like a lot of admins I run automated scripts for many things from patching, to instance builds, domain builds, etc.  I restarted several instances during the maintenance window as part of a scheduled patching cycle.  All but one had come back online.  Puzzled I go to start the instance and receive the following message:

awsincapacity

Luckily as part of the patching process I had automatically taken an AMI backup so could spin up another version of the instance without any loss of data.

It serves as a reminder though that your demand for resources can outgrow the capacity of cloud services (albeit temporarily).  The scary part – a simple reboot was the way I found out, and prevented an instance from starting unless I did something fairly drastic.