I think here that your best bet is to use block storage volumes, equivalent to the Amazon EBS volumes if you have used those before. So, you may have the fixed root drive, but you can attach on the secondary 500GB block storage volume as a data partition. You should be able to specify the datadir in the /etc/my.cnf configuration file to point to a mount of the secondary 500GB block storage volume.

And you can create symlinks to other folders on the second drive, wherever you want to make it seamless.

ln -s /folderOnMainDrive/folder /mountedDrive/folder/folder

I have my website on a second drive, and while my system is set up to pull website files from the main drive, they are actually symlinks that point to the second drive.

To add another drive:
Click on “volumes”, then click on “add volume”

Wayne Sallee
Wayne@WayneSallee.com