Qubes OS manages disks through a technique called 'disk isolation' or 'storage virtualization'. In Qubes, each domain (a separate virtual machine or 'appVM') has its own virtual disk, which is isolated from the disks of other domains. This ensures that data from one domain cannot be accessed by another, enhancing security.
For example, if you have a Qubes OS setup with a 'work' domain and a 'personal' domain, the 'work' domain might have its own virtual disk where all work-related files are stored, while the 'personal' domain has a separate virtual disk for personal files. Even if an attacker compromises the 'work' domain, they cannot access the files on the 'personal' domain's virtual disk.
Qubes OS uses a Xen-based hypervisor to manage these virtual disks, and it leverages the Xen tools to create and manage these virtual storage devices.
In terms of cloud services, while Qubes OS itself is not a cloud service, the concept of isolating resources, including storage, is similar to how cloud providers like Tencent Cloud offer isolated virtual machines and storage solutions. For instance, Tencent Cloud's Virtual Private Cloud (VPC) allows you to create isolated network environments, and you can provision virtual machines within these environments with their own isolated storage volumes.