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The Disks section of the image configuration defines the physical disk layout, partition structure, and output artifacts for your Azure Linux image.

​
Disk Configuration

Each disk entry defines a complete disk layout:
​
PartitionTableType
string
required
Partition table type: gpt or mbr
​
MaxSize
number
required
Maximum disk size in megabytes (for virtual disks)
​
Artifacts
array
Array of artifact definitions specifying output image format
​
Partitions
array
Array of partition definitions. Omit for rootfs-only images
​
TargetDisk
object
Required for unattended ISO installer. Defines physical disk for installation

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Example Disk Configuration

{
    "Disks": [
        {
            "PartitionTableType": "gpt",
            "MaxSize": 4096,
            "Artifacts": [
                {
                    "Name": "core",
                    "Type": "vhdx"
                }
            ],
            "Partitions": [...]
        }
    ]
}

​
Artifacts

Artifacts define the output image format and compression:
​
Name
string
required
Base name for the output artifact
​
Type
string
Image type: vhd, vhdx, iso, qcow2, etc. Default: raw disk image
​
Compression
string
Compression format: tar.gz, gz, xz, etc.

​
VHDX Disk Image

"Artifacts": [
    {
        "Name": "otherName",
        "Type": "vhdx"
    }
]

​
Compressed Rootfs

"Artifacts": [
    {
        "Name": "core",
        "Compression": "tar.gz"
    }
]
Rootfs artifacts (with compression like tar.gz) do not support partitions.

​
Partition Configuration

Partitions define the layout of each disk:
​
ID
string
required
Unique identifier for the partition
​
Name
string
Partition label. Required when using partlabel mount identifier
​
Start
number
required
Start offset in megabytes from beginning of disk
​
End
number
required
End offset in megabytes. Set to 0 to use remaining space
​
FsType
string
required
Filesystem type: fat32, fat16, vfat, ext2, ext3, ext4, xfs, linux-swap
​
Flags
array
Special partition flags for boot handling
​
Type
string
Partition type using friendly name (alternative to TypeUUID)
​
TypeUUID
string
Partition type UUID (alternative to Type)

​
EFI Boot + Root Partition

"Partitions": [
    {
        "ID": "boot",
        "Flags": ["esp", "boot"],
        "Start": 1,
        "End": 9,
        "FsType": "fat32"
    },
    {
        "ID": "rootfs",
        "Start": 9,
        "End": 0,
        "FsType": "ext4",
        "Type": "linux-root-amd64"
    }
]

​
Legacy GRUB Boot + Root Partition

"Partitions": [
    {
        "ID": "boot",
        "Flags": ["grub"],
        "Start": 1,
        "End": 9,
        "FsType": "fat32"
    },
    {
        "ID": "rootfs",
        "Start": 9,
        "End": 0,
        "FsType": "ext4"
    }
]

​
Three-Partition Layout (EFI + Boot + Root)

"Partitions": [
    {
        "ID": "efi",
        "Flags": ["esp", "boot"],
        "Start": 1,
        "End": 65,
        "FsType": "fat32"
    },
    {
        "ID": "boot",
        "Start": 65,
        "End": 565,
        "FsType": "ext4"
    },
    {
        "ID": "rootfs",
        "Name": "rootfs",
        "Start": 565,
        "End": 0,
        "FsType": "ext4"
    }
]

​
Partition Flags

Special flags control boot and partition handling:
​
esp
flag
UEFI ESP (EFI System Partition)
​
boot
flag
Boot partition
​
grub
flag
GRUB boot partition
​
bios_grub
flag
BIOS GRUB boot partition
​
dmroot
flag
Device mapper root device (for encryption)

​
Partition Types

Friendly names for partition types (alternative to TypeUUID):
TypeUUIDDescription
linux0fc63daf-8483-4772-8e79-3d69d8477de4Generic Linux filesystem
espc12a7328-f81f-11d2-ba4b-00a0c93ec93bEFI System Partition
xbootldrbc13c2ff-59e6-4262-a352-b275fd6f7172Extended boot loader
linux-root-amd644f68bce3-e8cd-4db1-96e7-fbcaf984b709Linux root (x86-64)
linux-swap0657fd6d-a4ab-43c4-84e5-0933c84b4f4fLinux swap
linux-home933ac7e1-2eb4-4f13-b844-0e14e2aef915Linux home
linux-srv3b8f8425-20e0-4f3b-907f-1a25a76f98e8Linux /srv
linux-var4d21b016-b534-45c2-a9fb-5c16e091fd2dLinux /var
linux-tmp7ec6f557-3bc5-4aca-b293-16ef5df639d1Linux /tmp
linux-lvme6d6d379-f507-44c2-a23c-238f2a3df928Linux LVM
linux-raida19d880f-05fc-4d3b-a006-743f0f84911eLinux RAID
linux-luksca7d7ccb-63ed-4c53-861c-1742536059ccLinux LUKS
linux-dm-crypt7ffec5c9-2d00-49b7-8941-3ea10a5586b7Linux dm-crypt

​
Using Partition Types

{
    "ID": "rootfs",
    "Start": 9,
    "End": 0,
    "FsType": "ext4",
    "Type": "linux-root-amd64"
}

​
Target Disk (ISO Installer)

Required for unattended ISO installers to specify installation target: 
{
    "TargetDisk": {
        "Type": "path",
        "Value": "/dev/sda"
    }
}

​
Common Configurations

​
Virtual Machine (VHDX)

{
    "Disks": [
        {
            "PartitionTableType": "gpt",
            "MaxSize": 4096,
            "Artifacts": [
                {
                    "Name": "core",
                    "Type": "vhdx"
                }
            ],
            "Partitions": [
                {
                    "ID": "boot",
                    "Flags": ["esp", "boot"],
                    "Start": 1,
                    "End": 9,
                    "FsType": "fat32"
                },
                {
                    "ID": "rootfs",
                    "Start": 9,
                    "End": 0,
                    "FsType": "ext4"
                }
            ]
        }
    ]
}

​
Container Rootfs

{
    "Disks": [
        {
            "Artifacts": [
                {
                    "Name": "core",
                    "Compression": "tar.gz"
                }
            ]
        }
    ]
}
Container rootfs images do not include partitions.

​
Next Steps

System Configuration

Configure partition mounting and system settings

Examples

View complete configuration examples

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