Using RSync and BitLocker for Windows with OSX

I tend to mainly use a Mac but also use a small Windows PC, particularly if I am on the road and don’t really want to carry and laptop case.

The MacBook I use is a MacBook 12″ with an M7 processor and 16GB of memory. It is adequate enough for light development tasks and normal day to day business life.

The Windows machine is a GPD Pocket 2 Amber Black. It’s a small 7″ machine that is perfectly capable in its own right and capable of connecting back to Mac if I need it to as well as being able to run desktop class Apps.

The GPD Pocket can take a Micro SD card, and I wanted to sync my entire document directory from the Mac to the SD card so that no matter how esoteric a document I needed, it was easy to find it as I always had what I needed with me.

To that end I wanted to ensure that this workflow was secure and that If I lost any device I would know that the device itself was locked down with the only option being to reformat the device rather than steal data.

The MacBook and windows were already set to use encrypted disks. Windows using BitLocker and the Mac using FileVault.

The MicroSD card however presented me a challenge. I needed it to be encrypted and to work with Windows and Mac and I took a look at various ways to do this and I settled upon using BitLocker again on the MicroSD card. Once setup this requires you to enter your BitLocker key to unlock the MicroSD card every time windows is booted. I should also note that Bitlocker requires a minimum of Windows 10 Professional.

The Mac does not support BitLocker but there is an App called M3 BitLocker Loader that supports BitLocker on the Mac. Once you plug the MicroSD into a USB that support SD or MicroSD cards it becomes visible to OSX and M3 BitLocker will detect it and invite you to enter your BitLocker Key.

Once this is done the M3 Bitlocker technology opens and mounts the Micro SD card using FUSE (it requires OSX FUSE)

Once the Bitlocker mounted drive is available to OSX you can then use rsync to sychronise directories from OSX to the Micro SD card, and they will of course be encrypted using the Bitlocker key:

rsync -rv  /Users/jimliddle/Documents/SME/"DIR to Sync from"  /Volumes/m3_bitlocker_disk2s1_/DIRToSyncTo

Once completed eject and remove the mount and plug the MicroSD back into the Windows Laptop, enter your BitLocker key and you are good to go.

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