Bootable rescue media is a removable drive containing boot files. When your Mac does not start, you use the drive to boot the Acronis recovery environment and recover your Mac from a previously created backup.
If you do not have a backup yet, please create it. Refer to Backing up to local or network storage and Backing up to Acronis Cloud for details.
Using bootable media is the only way to recover your Mac from an Acronis True Image 2016 backup.
To create Acronis bootable rescue media:
The drive must have 4 GB (or more) of free space. For example, you can use an external hard drive or a USB flash drive. Note that CD and DVD media are not supported.

We recommend that you create a new rescue media every time you upgrade your Mac OS X to a newer version. Otherwise, your rescue media may not work properly.