__S3 Integration Overview:__\\
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⚠️ General restrictions: This integration allows you to use an Amazon S3 bucket as the backend virtual file system ([VFS]) in CrushFTP. However, since S3 is not a true hierarchical file system, folder structures are simulated using object key prefixes. These are not limitations imposed by CrushFTP, but inherent to S3’s object storage architecture, which is optimized for static content access, not for dynamic file manipulation.\\
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__⚠️ Proxy Configuration:__ If your server accesses the internet through a proxy, ensure that the necessary S3 domains are whitelisted to allow successful communication with the S3 REST API.\\
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!1. S3 Configuration.\\
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The URL should be structured as follows (replace placeholders with your actual values):\\
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{{{
General S3 : s3://ACCESS_KEY_ID:SEECRET_ACCESS_KEY@SERVER/BUCKET/

Amazon S3 Example: s3://AKIAEXAMPLE:abcd1234example@s3.amazonaws.com/my-bucket/
}}}
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The security credentials (Access key ID and Secret Access Key) were offered to save at S3 user creation. The server and bucket information can be found on the S3 portal (at AWS site S3 -> Buckets).\\
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[attachments|S3_bucket_info.png]\\
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__Amazon EC2 IAM Authentication Support:__\\
CrushFTP also supports __IAM role-based__ authentication for S3 access on __EC2 instances__, although it is not enabled by default.\\
To use this mode:\\
• Set the S3 Username to: __iam_lookup__\\
• Set the S3 Password to: __lookup__\\
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This instructs CrushFTP to __automatically retrieve temporary credentials from the EC2 instance’s IAM role__ via the instance metadata service. Use this approach to securely avoid hardcoding static credentials in environments where IAM roles are configured properly.\\
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Then paste them on the appropriate fields in CrushFTP.\\
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[attachments|S3_VFS_config.png]\\
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The following policy permissions are needed on S3:\\
{{{
"s3:GetBucketLocation",
"s3:ListAllMyBuckets",
"s3:ListBucket",
"s3:ListBucketMultipartUploads",
"s3:PutObject",
"s3:AbortMultipartUpload",
"s3:ListMultipartUploadParts",
"s3:DeleteObject",
"s3:GetObject",
"s3:GetObjectAttributes"
}}}\\
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!2. Access other cloud storage through S3 REST API\\
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Google Cloud - [Google Cloud Storage Access Through S3 REST API | https://www.crushftp.com/crush11wiki/Wiki.jsp?page=Google%20Cloud%20Storage%20Integration#section-Google+Cloud+Storage+Integration-2.AccessThroughS3RESTAPI] \\
BackBlaze(b2) - [BackBlaze(b2) integration]\\
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!3. Assume Role access\\
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You can use IAM roles to delegate access to your AWS resources. With IAM roles, you can establish trust relationships between your trusting account and other AWS trusted accounts. (for more info see: [https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_create_for-user.html], and [https://docs.aws.amazon.com/STS/latest/APIReference/API_AssumeRole.html])\\
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Create the assume role at __Identity and Access Management (IAM)__:\\
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[attachments|create_assume_role.png]\\
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[attachments|assume_role_entity_type.png]\\
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[attachments|assume_role_s3_access.png]\\
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[attachments|assume_create_role_final_check.png]\\
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Add permission policy to the specified user. This policy will use the above-created assume role.\\
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[attachments|assume_role_user_permission_policy.png]\\
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{{{
{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "Statement1",
            "Effect": "Allow",
            "Action": "sts:AssumeRole",
            "Resource": "arn:aws:iam::XXXXX:role/AssumeRoleS3"
        }
    ]
}
}}}\\
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Use the specified user's Access key and Secret along with the Assume Role ARN to obtain S3 access.\\
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[attachments|assume_role_vfs_settings.png]\\
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