libvirt/docs/formatstoragecaps.rst

Storage Pool Capabilities XML format

Overview

The Storage Pool Capabilities XML will provide the information to determine what types of Storage Pools exist, whether the pool is supported, and if relevant the source format types, the required source elements, and the target volume format types.

Element and attribute overview

A query interface was added to the virConnect API's to retrieve the XML listing of the set of Storage Pool Capabilities ( Since 5.2.0 ):

virConnectGetStoragePoolCapabilities (API docs)

The root element that emulator capability XML document starts with is named storagepoolCapabilities. There will be any number of pool child elements with two attributes type and supported. Each pool element may have a poolOptions or volOptions subelements to describe the available features. Sample XML output is:

<storagepoolCapabilities>
  <pool type='dir' supported='yes'>
    <volOptions>
      <defaultFormat type='raw'</>
      <enum name='targetFormatType'>
        <value>none</value>
        <value>raw</value>
        ...
      </enum>
    </volOptions>
  </pool>
  <pool type='fs' supported='yes'>
    <poolOptions>
      <defaultFormat type='auto'</>
      <enum name='sourceFormatType'>
        <value>auto</value>
        <value>ext2</value>
        ...
      </enum>
    </poolOptions>
    <volOptions>
      <defaultFormat type='raw'</>
      <enum name='targetFormatType'>
        <value>none</value>
        <value>raw</value>
        ...
      </enum>
    </volOptions>
  </pool>
  ...
</storagepoolCapabilities>

The following section describes subelements of the poolOptions and volOptions subelements

defaultFormat

For the poolOptions, the type attribute describes the default format name used for the pool source. For the volOptions, the type attribute describes the default volume name used for each volume.

enum

Each enum uses a name from the list below with any number of value value subelements describing the valid values.

sourceFormatType

Lists all the possible poolOptions source pool format types.

targetFormatType

Lists all the possible volOptions target volume format types.