az disk --help Manage Azure Managed Disks.

[addaxnasom]

Group
    az disk : Manage Azure Managed Disks.
        Azure Virtual Machines use disks as a place to store an operating system, applications, and
        data. All Azure virtual machines have at least two disks: An operating system disk, and a
        temporary disk. The operating system disk is created from an image, and both the operating
        system disk and the image are actually virtual hard disks (VHDs) stored in an Azure storage
        account. Virtual machines also can have one or more data disks, that are also stored as
        VHDs.
        Azure Managed and Unmanaged Data Disks have a maximum size of 4095 GB (with the exception of
        larger disks in preview). Azure Unmanaged Disks also have a maximum capacity of 4095 GB.
        For more information, see:
        - Azure Disks - https://docs.microsoft.com/azure/virtual-machines/linux/about-disks-and-vhds
        and https://docs.microsoft.com/azure/virtual-machines/windows/about-disks-and-vhds.
        - Larger Managed Disks in Public Preview - https://azure.microsoft.com/blog/introducing-the-
        public-preview-of-larger-managed-disks-sizes/
        - Ultra SSD Managed Disks in Public Preview - https://docs.microsoft.com/azure/virtual-
        machines/windows/disks-ultra-ssd.

Commands:
    create        : Create a managed disk.
    delete        : Delete a managed disk.
    grant-access  : Grant a resource access to a managed disk.
    list          : List managed disks.
    revoke-access : Revoke a resource's read access to a managed disk.
    show          : Gets information about a disk.
    update        : Update a managed disk.
    wait          : Place the CLI in a waiting state until a condition of a managed disk is met.