EC2からS3の特定のバケットにからバックアップをするだけのユーザポリシー

s3cmd_backup.json

{
  "Version": "2012-10-17",
  "Statement": [
    {
      "Action": [
        "s3:*"
      ],
      "Sid": "Stmt1381276881000",
      "Resource": [
        "arn:aws:s3:::your s3 backet"
      ],
      "Effect": "Allow"
    },
    {
      "Action": [
        "s3:*"
      ],
      "Sid": "Stmt1381276927000",
      "Resource": [
        "arn:aws:s3:::your s3 backet/*"
      ],
      "Effect": "Allow"
    },
    {
      "Action": [
        "s3:ListAllMyBuckets"
      ],
      "Sid": "Stmt1381276958000",
      "Resource": [
        "arn:aws:s3:::*"
      ],
      "Effect": "Allow"
    }
  ]
}