> For the complete documentation index, see [llms.txt](https://platform9.com/kb/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://platform9.com/kb/pmo/how-to/identify-block-device-of-volume-attached-to-instance.md).

# Identify Block Device of Volume Attached to Instance

## Problem

The block device of an attached/mounted volume for a particular instance needs to be identified.

## Environment

* Platform9 Managed OpenStack - All Versions
* Nova
* Cinder
* Libvirt

## Procedure

1. Login to the KVM host.
2. Identify the disk ID within the instance's XML file.

{% tabs %}
{% tab title="None" %}

```none
# ls -l/opt/pf9/data/instances/[INSTANCE_UUID]/cfg-[INSTANCE_UUID].xml
```

{% endtab %}
{% endtabs %}

Example:

{% tabs %}
{% tab title="None" %}

```none
/opt/pf9/data/instances/8f9dadb1-1bfa-45b9-8fed-cd53c38de547/cfg-8f9dadb1-1bfa-45b9-8fed-cd53c38de547.xml[disk type='block' device='disk'] [driver name='qemu' type='raw' cache='none' io='native'/] [source dev='/dev/disk/by-id/dm-uuid-mpath-3624a9370ebcccad586e4418c0002d81b'/]   [target dev='vda' bus='virtio'/] [serial]8837dded-d387-4b3c-a8f9-9b91f0142240[/serial] [address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/][/disk]
```

{% endtab %}
{% endtabs %}

3. Look for the 'source dev line' for the ***disk id**.* In the above example, it is ' *3624a9370ebcccad586e4418c0002d81b.'*
4. Run\*\*`lsblk`\*\* command to get all the disks and partitions.

{% tabs %}
{% tab title="None" %}

```none
# lsblk sdp 8:240 0 50G 0 disk └─3624a9370ebcccad586e4418c0002d81f 253:31 0 50G 0 mpath └─3624a9370ebcccad586e4418c0002d81f1 253:32 0 50G 0 part
```

{% endtab %}
{% endtabs %}


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