-
Hello Giada,
Good day!
Yes, you are right—the issue in the question is related to the vCPU limit.
As of 2019, AWS moved to vCPU-based limits for On-Demand EC2 instances. These limits are applied at the regional. See https://aws.amazon.com/ec2/faqs/#How_many_instances_can_I_run_in_Amazon_EC2
The failure after 20 instances suggests that the total number of vCPUs required by the instances exceeded the region’s vCPU limit. This limit is often more restrictive, especially when launching many instances of high-performance instance types, which consume more vCPUs. As a result, the vCPU limit is more likely the cause of the failure, not the number of instances.
Hence, the correct answer is: There is a vCPU-based On-Demand Instance limit per region, which is why subsequent requests failed. The solution is to submit a limit increase request to AWS, and once it’s approved, you can retry the failed requests.
Based on the snippet, your answer is “Select a different Availability Zone and retry the failed request. Simply choosing another Availability Zone might not resolve the issue if the vCPU limit is still being exceeded. Therefore, requesting a limit increase for vCPUs is the more appropriate solution.
I hope this helps.
Regards,
Neil @ Tutorials Dojo
