[virt-tools-list] Is the default of "format" raw? (virt-install)

[Peng Yu]

Hi,

`man virt-install` says the following. But it is not clear to me what
format is used if it is not specified explicitly. Does anybody know?
Should this be documented?

Also, how to check what the format is of an image file? Thanks.

format
  Image format to be used if creating managed storage. For file
  volumes, this can be 'raw', 'qcow2', 'vmdk', etc. See format
  types in <http://libvirt.org/storage.html> for possible values.
  This is often mapped to the driver_type value as well.

  With libvirt 0.8.3 and later, this option should be specified if
  reusing an existing disk image, since libvirt does not autodetect
  storage format as it is a potential security issue. For example,
  if reusing an existing qcow2 image, you will want to specify
  format=qcow2, otherwise the hypervisor may not be able to read
  your disk image.

-- 
Regards,
Peng