# Managing the Advanced Threat Defense Appliance disks

The Advanced Threat Defense Appliance has two disks referred to as disk-A and disk-B. Disk-A is the active disk and disk-B is the backup disk. Even if disk-A is not booted, it is referred as the active disk. Similarly, even if disk-B is the booted disk, it is referred as the backup disk. By default, both these disks contain the pre-installed software version.

Use the show command to view the software version stored in the active and backup disks.

Table 1: CLI commands for managing the disks
Command Description
copyto backup Copies the software version on the active disk to the backup disk. For example, if you find the current active software version to be stable, you can back it up to the backup disk.
Note: This command works only if the appliance had been booted from the active disk.
copyto active Copies the software version from the backup disk to the active disk. However, you must restart the Advanced Threat Defense Appliance for it to load this new image from the active disk.
Note: This command works only if the appliance had been booted from the backup disk.