EKS Cluster nodegroup - AMI release version - How to keep the EBS customize size

Hello,

When you create a managed node group (without using custom launch template) EKS will create a default launch template for the Autoscaling group based on the node group configurations you provide.

Creation of node group from AWS console involves the following steps;

Step 1 : Configure node group

Step 2 : Set compute and scaling configuration

Step 3 : Specify networking

Step 4 : Review and create

In step 2, users can define the "Disk Size" which will be the size of the attached EBS volume for each node. You can increase or decrease the default size based on your use case.

Once you create a managed node group with the above configuration a default launch template will be created which will be used by the Autoscaling group. It is not recommended to change the configurations of a default launch template that is created by EKS. This will be considered out of band changes.

• Is there a way to define the value or keep the customized size before updating the node group - AMI release version?

When a new AMI is available there will be an option to update the AMI release version of the node group. This will be the case for managed node groups and you will not see the same option when using managed node groups with custom launch templates and self managed nodes.

When you update the AMI release version it should update the AMI version for the node group and should not change the disk size that you have set during the node group creation. The updated node group should also have the same size that was specified during creation however, with a new AMI version.

1. In order to keep your custom size you can create a node group with your custom size requirement which can be set in step 2 of node group creation.

OR

2. For the highest level of customization, you can deploy managed nodes using your own launch template. This allows you to customize the configurations including AMI and disk size [1].

[1] Customizing managed nodes with launch templates - https://docs.aws.amazon.com/eks/latest/userguide/launch-templates.html