Talos Linux provides tools to observe available disks and volumes on the machine.

​
Listing Disks

To obtain a list of all available block devices (disks) on the machine, you can use the following command: 
$ talosctl get disks
NODE         NAMESPACE   TYPE   ID        VERSION   SIZE    READ ONLY   TRANSPORT   ROTATIONAL   WWID                                                               MODEL            SERIAL
172.20.0.5   runtime     Disk   loop0     1         75 MB   true
172.20.0.5   runtime     Disk   nvme0n1   1         10 GB   false       nvme                     nvme.1b36-6465616462656566-51454d55204e564d65204374726c-00000001   QEMU NVMe Ctrl   deadbeef
172.20.0.5   runtime     Disk   sda       1         10 GB   false       virtio      true                                                                            QEMU HARDDISK
172.20.0.5   runtime     Disk   sdb       1         10 GB   false       sata        true         t10.ATA     QEMU HARDDISK                           QM00013        QEMU HARDDISK
172.20.0.5   runtime     Disk   sdc       1         10 GB   false       sata        true         t10.ATA     QEMU HARDDISK                           QM00001        QEMU HARDDISK
172.20.0.5   runtime     Disk   vda       1         13 GB   false       virtio      true
To obtain detailed information about a specific disk, execute the following command: 
# talosctl get disk sda -o yaml
node: 172.20.0.5
metadata:
    namespace: runtime
    type: Disks.block.talos.dev
    id: sda
    version: 1
    owner: block.DisksController
    phase: running
    created: 2024-08-29T13:06:43Z
    updated: 2024-08-29T13:06:43Z
spec:
    dev_path: /dev/sda
    size: 10485760000
    human_size: 10 GB
    io_size: 512
    sector_size: 512
    readonly: false
    cdrom: false
    model: QEMU HARDDISK
    modalias: scsi:t-0x00
    bus_path: /pci0000:00/0000:00:07.0/virtio4/host1/target1:0:0/1:0:0:0
    sub_system: /sys/class/block
    transport: virtio
    rotational: true
    symlinks:
        - /dev/disk/by-diskseq/10
        - /dev/disk/by-path/pci-0000:00:07.0
        - /dev/disk/by-path/virtio-pci-0000:00:07.0

​
Discovered Volumes

Talos Linux monitors all block devices and partitions on the machine. Details about these devices, including their type, can be found in the DiscoveredVolume resource. 
$ talosctl get discoveredvolumes
NODE         NAMESPACE   TYPE               ID        VERSION   TYPE        SIZE     DISCOVERED   LABEL       PARTITIONLABEL
172.20.0.5   runtime     DiscoveredVolume   dm-0      1         disk        88 MB    xfs          STATE
172.20.0.5   runtime     DiscoveredVolume   loop0     1         disk        75 MB    squashfs
172.20.0.5   runtime     DiscoveredVolume   nvme0n1   1         disk        10 GB
172.20.0.5   runtime     DiscoveredVolume   sda       1         disk        10 GB
172.20.0.5   runtime     DiscoveredVolume   sdb       1         disk        10 GB
172.20.0.5   runtime     DiscoveredVolume   sdc       1         disk        2.1 GB   gpt
172.20.0.5   runtime     DiscoveredVolume   sdc1      1         partition   957 MB   xfs
172.20.0.5   runtime     DiscoveredVolume   sdc2      1         partition   957 MB   xfs
172.20.0.5   runtime     DiscoveredVolume   sdd       1         disk        1.0 GB   gpt
172.20.0.5   runtime     DiscoveredVolume   sdd1      1         partition   957 MB   xfs
172.20.0.5   runtime     DiscoveredVolume   sde       1         disk        10 GB
172.20.0.5   runtime     DiscoveredVolume   vda       1         disk        13 GB    gpt
172.20.0.5   runtime     DiscoveredVolume   vda1      1         partition   105 MB   vfat                     EFI
172.20.0.5   runtime     DiscoveredVolume   vda2      1         partition   1.0 MB                            BIOS
172.20.0.5   runtime     DiscoveredVolume   vda3      1         partition   982 MB   xfs          BOOT        BOOT
172.20.0.5   runtime     DiscoveredVolume   vda4      2         partition   1.0 MB   talosmeta                META
172.20.0.5   runtime     DiscoveredVolume   vda5      1         partition   105 MB   luks                     STATE
172.20.0.5   runtime     DiscoveredVolume   vda6      1         partition   12 GB    xfs          EPHEMERAL   EPHEMERAL
Talos Linux has built-in automatic detection for various filesystem types and GPT partition tables. Currently, the following filesystem types are supported:
  • bluestore (Ceph)
  • ext2, ext3, ext4
  • iso9660
  • luks (LUKS encrypted partition)
  • lvm2
  • squashfs
  • swap
  • talosmeta (Talos Linux META partition)
  • vfat
  • xfs
  • zfs
The discovered volumes can include both Talos-managed volumes and any other volumes present on the machine, such as Ceph volumes.

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Disk Layout

The default disk layout for Talos installation is as follows: 
+-----------------------------------------------------------------------------+
| Physical Disk (1TB)                                                         |
+=============+===========+==========+========================================+
| EFI (boot)  | META      | STATE    | EPHEMERAL (spans the rest of the disk) |
| [~1GB]      | [~1MB]    | [~100MB] | [~998GB]                               |
+-------------+-----------+----------+----------------------------------------+
In this diagram:
  • EFI: the EFI partition used for booting the system.
  • META: the partition used for storing Talos metadata.
  • STATE: the partition used for storing the system state, including machine configuration.
  • EPHEMERAL: the partition used for storing container data, downloaded images, logs, etcd data (for controlplane nodes) etc.
Talos Linux hardcodes the partition layout for the EFI, META, and STATE partitions. The EPHEMERAL partition by default consumes all unallocated space, but it can be created on another disk or resized. The EPHEMERAL partition is a catch-all location for storing data, while it might be desired to segregate the data into different partitions. Talos supports creating additional user volumes to be used for different purposes: e.g. local storage for various applications, specific volumes per applications, etc.

​
Single Disk Layout

+-------------------------------------------------------------------------------------------------------+
| Physical Disk (1TB)                                                                                   |
+=============+===========+==========+============+===========+===============+=========================+
| EFI (boot)  | META      | STATE    | EPHEMERAL  | csi-data  | local-storage | << Unallocated Space >> |
| [~1GB]      | [~1MB]    | [~100MB] | [~200GB]   | [~100GB]  | [~200GB]      | [~500GB]                |
+-------------+-----------+----------+------------+-----------+---------------+-------------------------+
In this layout, the EPHEMERAL partition was limited to 200GB, and two additional partitions were created for csi-data and local-storage.

​
Multiple Disk Layout

+---------------------------------------------------------------------------------------+
| Physical Disk 1 (1TB)                                                                 |
+=============+===========+==========+============+===========+=========================+
| EFI (boot)  | META      | STATE    | EPHEMERAL  | csi-data  | << Unallocated Space >> |
| [~1GB]      | [~1MB]    | [~100MB] | [~500GB]   | [~100GB]  | [~400GB]                |
+-------------+-----------+----------+------------+-----------+-------------------------+
| Physical Disk 2 (1TB)                                                                 |
+===============+=======================================================================+
| local-storage | << Unallocated Space >>                                               |
| [~500GB]      |  [~500GB]                                                             |
+---------------+-----------------------------------------------------------------------+
In this layout, the EPHEMERAL partition was limited to 500GB, and two additional partitions were created for csi-data and local-storage, and they were created on different disks.