Home > Storage > PowerScale (Isilon) > Product Documentation > Cloud > APEX File Storage for AWS: Deployment Guide > Prepare cluster nodes block device mapping
If you use AWS CLI to perform the deployment, the block device mapping json file is required.
OneFS uses EBS as data volumes. All EC2 instances in a cluster must share the same configuration of block device mapping. See AWS block device mapping documentation for more details.
To prepare the block device mapping json file, you can modify the content of section block-device-mappings-template.json by replacing the below items with your settings:
Save the modified content to the block-device-mappings.json file. In this guide, we assume the file path is C:\json-files-template\block-device-mappings.json
Note: the block-device-mappings-template.json content is a template for six volumes only; you can add more volumes as needed. You can also specify a throughput and IOPS configuration for gp3.
To enable EBS encryption, you need to add the following EBS options in the block device mapping based on your key type: AWS managed keys or customer managed keys.