SpinRite is an excellent disk maintenance and recovery tool provided by Steve Gibson over at https://www.grc.com. There are many success stories from its use provided by Steve frequently on his Security Now! podcast.
There are various guides online for running SpinRite on a Mac but none that I found worked exactly as described, so this is my guide based on how I got SpinRite to work on my Mac. The basic principle is to set up a virtual machine on your Mac and give it raw block access to the disk and then run SpinRite as normal within the VM.
This guide is written using the following versions of software so your experience may differ if you are using different versions:
MacOS Sierra 10.12.6
VirtualBox 5.1.26 r117224
This guide is designed for more advanced users as granting anything raw block access to a disk can be dangerous, especially if you select the wrong disk! Please be careful while following these steps.
This guide does rely on you connecting the hard disk up to your Mac via USB using a caddy. It may be that the disk is so far gone that it will not mount in MacOS and if that is the case you will not be able to use this guide. However it may still be possible to run SpinRite on it by connecting it directly to the motherboard of another computer via SATA or IDE.
Creating an ISO from the SpinRite.exe provided
When you first purchase and download SpinRite you are given the file SpinRite.exe to run which you can use to install locally or create an ISO to boot from. The easiest way to get the ISO is to run SpinRite.exe on any Windows system you have available, or even a Windows VM running on your Mac and copy the SpinRite.iso file across to your Mac. However if that simply is not possible for you an alternative way is to run SpinRite.exe in Wine on your Mac. I prefer the implementation provide by PlayOnMac so I will be using that in this guide. If you can create the ISO in Windows skip ahead to the next section.
The first step is to download and install PlayOnMac. Once you have it, launch it and select Install a program. In the new window that comes up click on Install a non-listed program.
Click Next on both “Please read this” windows then Next again when the Manual Installation wizard comes up. Select Install a program in a new virtual drive and click Next. Give it a name (SpinRite will do) and click Next. Do not tick any of the before installation options and click Next. Select 32 bits windows installation and click Next. Click Cancel on any additional installations that Wine prompts you about (such as Wine Gecko) until you reach the select set-up file to run screen.
Click Browse and select your SpinRite.exe file.
When you click Next SpinRite will launch!
Click Create ISO or IMG File and then Save a Boot Image File. When the folder structure appears select Users > your username > Desktop to save the SpinRite.iso file to the desktop on your Mac. Once that has been successfully created exit SpinRite and PlayOnMac.
Running SpinRite on your Mac in a VirtualBox VM
The first step here is to download and install VirtualBox. There is nothing special about the installation so just follow the wizard through without changing any of the options.
Attach the hard disk you want to run SpinRite on by connecting it to a USB caddy and plugging the USB into your Mac. Unplug any other external drive you may have connected. Next, open Terminal and enter the command
diskutil list to see the disks attached to your Mac. The disks prefixed with external will be the one you have connected up, followed by physical or virtual. In my example these are /dev/disk4 (physical) and /dev/disk5 (virtual). You may have multiple virtual entries depending on how many partitions are on the disk. You can also use the size of the disk to verify it is the correct one. Write down each of the disk identifiers that relate to the external drive.
The next step is to unmount the virtual disk partitions, but not the physical disk. In my case that means unmounting /dev/disk5. To do this type
diskutil unmountdisk /dev/disk5. Repeat this for any other virtual disk partitions your drive has.
Now you need to create a vmdk file that will be attached to the virtual machine. This vmdk will direct all input and output to the physical disk you have connected. This is done using the following command:
sudo /usr/local/bin/VBoxManage internalcommands createrawvmdk -filename RawDisk.vmdk -rawdisk /dev/disk4
Note that for this command you must use the disk identifier for the physical disk and not any of the virtual disks. In my case this is /dev/disk4. If you get an error stating VERR_RESOURCE_BUSY make sure have you have unmounted every virtual disk. When you run the command you will be prompted for your password, enter it and press enter.
This will create a file RawDisk.vmdk in the root of your home directory. This will also re-mount the disk. Unmount it again using
diskutil unmountdisk /dev/disk5 (virtual ones again).
Now you need to launch VirtualBox as root which can also be done using Terminal. This is required to allow read and write access to a raw device. Launch VirtualBox using the following command:
Do not close this Terminal window. As VirtualBox was launched through Terminal you must keep Terminal open throughout the rest of the process and while using SpinRite.
Create a new VM by clicking New, give it a name, select Other under Type and under version select DOS, then click Continue.
Under Memory size the default of 32 MB is more than enough so accept that and click Continue.
Under Hard disk select Use an existing virtual hard disk file and click on the little folder icon next to it to bring up the file selection prompt.
As you are running VirtualBox under root you will be taken to the folder structure for the root user account. However the RawDisk.vmdk file is saved in your user area. At the top of the file selection window click on the drop down box and select Macintosh HD (or whatever your Mac’s hard drive is called). From there select Users > your username.
In this folder you should find RawDisk.vmdk. Click on Open.
If you get an error VERR_RESOURCE_BUSY when trying to open RawDisk.vmdk make sure that the external virtual disks haven’t been mounted again (check using
diskutil list and fix using the same
diskutil unmountdisk command as before).
As soon as you click Open Mac OS will actually remount the disk – how annoying! This must be rectified again by using the command the same way as before. In my case it is
diskutil unmountdisk /dev/disk5. You will have to do this in a new Terminal window as you can no longer interact with the one you launched VirtualBox from until you close VirtualBox.
Once that is done click Create.
Open Settings for the VM and go to Storage and select the CD icon underneath RawDisk.vmdk. Next to Optical Drive click on the small CD icon and use the file explorer that pops up to select your SpinRite.iso file. Once that is done click on OK.
Power on the VM and it should automatically boot from the CD and launch SpinRite! Assuming you already know how to use SpinRite make your way through the menu and select the disk you have attached to your Mac.
Start the SpinRite process and let it do its magic!
That’s it for running SpinRite on your Mac. Phew! … Bring on the future releases of SpinRite 6.x and 7.0 for better Mac compatibility!