What are qcow2 images?

QCOW2 is a storage format for virtual disks. QCOW stands for QEMU copy-on-write. The QCOW2 format decouples the physical storage layer from the virtual layer by adding a mapping between logical and physical blocks.

What is difference between ISO and qcow2?

QCOW2 Formatted Virtual Machine Storage – is a storage format for virtual machine disk images. QCOW stands for “QEMU copy on write”. It is used with the KVM hypervisor. ISO – The ISO format is a disk image formatted with the read-only ISO 9660 filesystem which is used for CDs and DVDs.

What is QEMU image?

qcow is a file format for disk image files used by QEMU, a hosted virtual machine monitor. It stands for “QEMU Copy On Write” and uses a disk storage optimization strategy that delays allocation of storage until it is actually needed.

What extension is qcow2?

A QCOW2 file is a disk image saved in the second version of the QEMU Copy On Write (QCOW2) format, which is used by QEMU virtualization software. It stores the hard drive contents of a QEMU virtual machine.

How do I convert an image to qcow2?


  1. Run the following command to convert the image file format to QCOW2: qemu-img convert -p -f vmdk -O qcow2 centos6.9.vmdk centos6.9.qcow2. The parameters are described as follows:
  2. Run the following command to query details about the converted image file in QCOW2 format: qemu-img info centos6.9.qcow2.

How do I use qcow2 image in vmware?

Time to attach the correct one. Edit settings for the VM and add a new device -> existing hard disk -> then select the vmdk we converted with vmkfstools above. Make any other changes and you should now be good to go. Remember to install vmware-tools on the VM and possibly remove qemu-guest as well!

How do I convert ISO to qcow2?

Convert . iso Image to . qcow2 Image

  1. No any direct command available to convert . iso to . qcow2 image so first convert it into raw image then raw image can be convert into qcow2 form.
  2. First Create a VDI image using VirtualBox: Create VM (In Virtual Box) using .iso image with VDI Hard disk file type as shown in below.

Is qcow2 compressed?

Only the qcow2 format supports encryption or compression. qcow2 encryption uses the AES format with secure 128-bit keys. qcow2 compression is read-only, so if a compressed sector is converted from qcow2 format, it is written to the new format as uncompressed data.

How do I use qcow2 image in openstack?

To create an image, use openstack image create:

  1. $ openstack image create imageName.
  2. $ openstack image set imageName.
  3. $ openstack image create –disk-format qcow2 –container-format bare \ –public –file ./centos63.qcow2 centos63-image.

How do I convert raw files to ISO?

Convert Image File to ISO

  1. Run PowerISO.
  2. Choose “Tools > Convert” Menu.
  3. PowerISO shows Image File to ISO Converter dialog.
  4. Choose the source image file you want to convert.
  5. Set the output file format to iso file.
  6. Choose the output iso file name.
  7. Click “OK” button to start converting.

Which is better qcow2 or raw image format?

qemu-img info /var/lib/libvirt/images/sample1.qcow2 In conclusion, Raw vs Qcow2: both have their pros and cons, while raw offers pure performance whereas qcow2 offers practical and useful features. In the end, use of image format comes down to use case scenario.

What are the optional features of qcow 2?

Optional features include zlib -based transparent decompression. qcow2 is an updated version of the qcow format. qcow2 supports AES encryption. The difference from the original version is that qcow2 supports multiple snapshots using a newer, more flexible model for storing them.

Which is more space efficient image or qcow2?

A qcow2 file will generally be more space efficient than an equivalent image file. While it is possible to create “sparse” image files, these are difficult to transfer in an efficient manner. A qcow2 relies on mechanisms other than sparse allocation to achieve “thin provisioning” and is thus easier to move around.

What are the different types of qcow files?

Files in qcow format can contain a variety of disk images which are generally associated with specific guest operating systems. Three versions of the format exist: qcow, qcow2 and qcow3 which use the .qcow, .qcow2 and .qcow3 file extensions, respectively.