From 55248e26a113c76803dc98daabb2d6938b1c3da5 Mon Sep 17 00:00:00 2001 From: Rich Hintz Date: Fri, 25 Nov 2016 15:29:31 -0800 Subject: [PATCH] Add ec2 gotcha - undocumented limit of zero for new accounts (#333) Document an undocumented restriction applicable to very new accounts, such as might be used in instruction. A teacher attempting to have students use their own brand new accounts to each launch one g2 instance reported that the student launches failed because of an undocumented soft limit of zero. This may be associated with AWS trying to mitigate the use of GPU instances for Bitcoin mining, though that's speculation. --- README.md | 1 + 1 file changed, 1 insertion(+) diff --git a/README.md b/README.md index 37d6ce6..5f8c703 100644 --- a/README.md +++ b/README.md @@ -778,6 +778,7 @@ EC2 - ❗⏱ Instances come in two types: **Fixed Performance Instances** (e.g. M3, C3, and R3) and [**Burstable Performance Instances**](https://aws.amazon.com/ec2/instance-types/#burst) (e.g. T2). A T2 instance receives CPU credits continuously, the rate of which depends on the instance size. T2 instances accrue CPU credits when they are idle, and use CPU credits when they are active. However, once an instance runs out of credits, you'll notice a severe degradation in performance. If you need consistently high CPU performance for applications such as video encoding, high volume websites or HPC applications, it is recommended to use Fixed Performance Instances. - 🔸An IAM role can be assigned to an EC2 instance [only at launch time](http://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_use_switch-role-ec2.html). You cannot assign to a running instance. - Instance user-data is [limited to 16 KB](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-instance-metadata.html#instancedata-add-user-data)(This limit applies to the data in raw form, not base64-encoded form). If more data is needed, it can be downloaded from S3 by a user-data script. +- Very new accounts may not be able to launch some instance types, such as GPU instances, because of an initially imposed “soft limit” of zero. This limit can be raised by making a support request. See [AWS Service Limits](http://docs.aws.amazon.com/general/latest/gr/aws_service_limits.html) for the method to make the support request. Note that this limit of zero is [not currently documented](http://docs.aws.amazon.com/general/latest/gr/aws_service_limits.html#limits_ec2). CloudWatch -------------------