EC2 instance creation - vCPU limit issue

It appears there might be a misunderstanding regarding the type of instances you're trying to launch. The quota increase you mentioned was for "All G and VT Spot Instance Requests," but it seems you're attempting to launch an On-Demand instance instead of a Spot instance.

Spot Instances and On-Demand Instances have separate quotas in Amazon EC2. The error message you're receiving suggests that your On-Demand Instance limit for the G instance family (which includes g5.xlarge) is currently set to 0 vCPUs.

To resolve this issue, you have a couple of options:

1. If you intended to launch a Spot Instance, make sure you're selecting the Spot option when creating your EC2 instance. This should allow you to use the 4 vCPU quota you've been granted for Spot Instances.

2. If you want to launch an On-Demand Instance, you'll need to request a quota increase specifically for On-Demand Instances in the G instance family. You can do this by:

   • Going to the EC2 console
   • Navigating to the Limits page
   • Finding the limit for "All G and VT On-Demand Instances"
   • Requesting an increase for this limit

Remember that AWS sets default limits on the number of instances you can run on a per-Region basis when you create your AWS account. These limits are separate for different instance types and purchasing options (On-Demand vs Spot).

If you're still encountering issues after verifying your instance type selection or requesting the appropriate quota increase, it's recommended to contact AWS Support for further assistance.
Sources
Troubleshoot Amazon EC2 instance launch issues - Amazon Elastic Compute Cloud
Resolve an InstanceLimitExceeded error on an EC2 instance | AWS re:Post

In addition to what the bot wrote, note that Spot Instances are essentially spare capacity that's available at a discounted price when there isn't better use for them. When demand for regular capacity increases, spot instances are automatically terminated or stopped, depending on how you configured your instance. This happens quite commonly.

It's important to recognise that spot instances will stop running in those situations and, depending on configuration, will even get terminated, which also deletes the attached EBS volumes by default.

The documentation for spot instances is available here: https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/using-spot-instances.html

To increase the limits, you have to visit the Service Quotas page:

https://XXXXXXXXXXXX-tdvxrefg.us-east-1.console.aws.amazon.com/servicequotas/home?region=us-east-1

Then select the service from dropdown menu - Amazon Ec2, and request for quota increase.

It will take some time to get this increase done.