Too many storage controllers of the type in Vagrant

I'm going to create 7 servers with 2 disks each. Here is the vagrant file. This is my first configuration of a multiple machines environments. Hence I haven't any experience in creating environments from scratch.

This is the error I got

Command: ["storagectl", "cc27c05a-63da-4e02-ab73-86843032e387", "--name", "SATA Controller", "--add", "sata"]

Stderr: VBoxManage: error: Too many storage controllers of this type
VBoxManage: error: Details: code NS_ERROR_INVALID_ARG (0x80070057), component StorageController, interface IStorageController, callee nsISupports
VBoxManage: error: Context: "AddStorageController(Bstr(pszCtl).raw(), StorageBus_SATA, ctl.asOutParam())" at line 1044 of file VBoxManageStorageController.cpp

Vagrafile

Vagrant.configure(2) do |config|

    config.vm.box = "ubuntu/trusty64"

    config.vm.provider "virtualbox" do |vb|
        vb.customize ["modifyvm", :id, "--memory", "2048", "--cpus", "1"]
        vb.customize ["storagectl", :id, "--name", "SATA Controller", "--add", "sata"]
    end

    config.vm.define "machine1" do |machine1|

        machine1.vm.hostname = "machine1"

        machine1.vm.provider "virtualbox" do |vb|
            vb.customize ["createhd",  "--filename", "machine1_disk0", "--size", 4096]
            vb.customize ["createhd",  "--filename", "machine1_disk1", "--size", 4096]
            vb.customize ["storageattach", :id, "--storagectl", "SATA Controller", "--port", 1, "--type", "hdd", "--medium", "machine1_disk0.vdi"]
            vb.customize ["storageattach", :id, "--storagectl", "SATA Controller", "--port", 2, "--type", "hdd", "--medium", "machine1_disk1.vdi"]
        end

        machine1.vm.network "private_network", ip: "192.168.10.10"
        machine1.vm.network "private_network", ip: "192.168.10.15"
    end

    config.vm.define "machine2" do |machine2|

        machine2.vm.hostname = "machine2"

        machine2.vm.provider "virtualbox" do |vb|
            vb.customize ["createhd",  "--filename", "machine2_disk0", "--size", 4096]
            vb.customize ["createhd",  "--filename", "machine2_disk1", "--size", 4096]
            vb.customize ["storageattach", :id, "--storagectl", "SATA Controller", "--port", 1, "--type", "hdd", "--medium", "machine2_disk0.vdi"]
            vb.customize ["storageattach", :id, "--storagectl", "SATA Controller", "--port", 2, "--type", "hdd", "--medium", "machine2_disk1.vdi"]
        end

        machine2.vm.network "private_network", ip: "192.168.10.20"
        machine2.vm.network "private_network", ip: "192.168.10.25"
    end

    config.vm.define "machine3" do |machine3|

        machine3.vm.hostname = "machine3"

        machine3.vm.provider "virtualbox" do |vb|
            vb.customize ["createhd",  "--filename", "machine3_disk0", "--size", 4096]
            vb.customize ["createhd",  "--filename", "machine3_disk1", "--size", 4096]
            vb.customize ["storageattach", :id, "--storagectl", "SATA Controller", "--port", 1, "--type", "hdd", "--medium", "machine3_disk0.vdi"]
            vb.customize ["storageattach", :id, "--storagectl", "SATA Controller", "--port", 2, "--type", "hdd", "--medium", "machine3_disk1.vdi"]
        end

        machine3.vm.network "private_network", ip: "192.168.10.30"
    end

    config.vm.define "machine4" do |machine4|

        machine4.vm.hostname = "machine4"

        machine4.vm.provider "virtualbox" do |vb|
            vb.customize ["createhd",  "--filename", "machine4_disk0", "--size", 4096]
            vb.customize ["createhd",  "--filename", "machine4_disk1", "--size", 4096]
            vb.customize ["storageattach", :id, "--storagectl", "SATA Controller", "--port", 1, "--type", "hdd", "--medium", "machine4_disk0.vdi"]
            vb.customize ["storageattach", :id, "--storagectl", "SATA Controller", "--port", 2, "--type", "hdd", "--medium", "machine4_disk1.vdi"]
        end

        machine4.vm.network "private_network", ip: "192.168.10.40"
    end

    config.vm.define "machine5" do |machine5|

        machine5.vm.hostname = "machine5"

        machine5.vm.provider "virtualbox" do |vb|
            vb.customize ["createhd",  "--filename", "machine5_disk0", "--size", 4096]
            vb.customize ["createhd",  "--filename", "machine5_disk1", "--size", 4096]
            vb.customize ["storageattach", :id, "--storagectl", "SATA Controller", "--port", 1, "--type", "hdd", "--medium", "machine5_disk0.vdi"]
            vb.customize ["storageattach", :id, "--storagectl", "SATA Controller", "--port", 2, "--type", "hdd", "--medium", "machine5_disk1.vdi"]
        end

        machine5.vm.network "private_network", ip: "192.168.10.50"
    end

    config.vm.define "machine6" do |machine6|

        machine6.vm.hostname = "machine6"

        machine6.vm.provider "virtualbox" do |vb|
            vb.customize ["createhd",  "--filename", "machine6_disk0", "--size", 4096]
            vb.customize ["createhd",  "--filename", "machine6_disk1", "--size", 4096]
            vb.customize ["storageattach", :id, "--storagectl", "SATA Controller", "--port", 1, "--type", "hdd", "--medium", "machine6_disk0.vdi"]
            vb.customize ["storageattach", :id, "--storagectl", "SATA Controller", "--port", 2, "--type", "hdd", "--medium", "machine6_disk1.vdi"]
        end

        machine6.vm.network "private_network", ip: "192.168.10.60"
    end

    config.vm.define "machine7" do |machine7|

        machine7.vm.hostname = "machine7"

        machine7.vm.provider "virtualbox" do |vb|
            vb.customize ["createhd",  "--filename", "machine7_disk0", "--size", 4096]
            vb.customize ["createhd",  "--filename", "machine7_disk1", "--size", 4096]
            vb.customize ["storageattach", :id, "--storagectl", "SATA Controller", "--port", 1, "--type", "hdd", "--medium", "machine7_disk0.vdi"]
            vb.customize ["storageattach", :id, "--storagectl", "SATA Controller", "--port", 2, "--type", "hdd", "--medium", "machine7_disk1.vdi"]
        end

        machine7.vm.network "private_network", ip: "192.168.10.70"
    end

end

The issue is that your box already have existing SATA storage controller, so you shouldn't try to add new one in the beginning of your provision (you cannot add multiple SATA storage controllers).