Converting Images
Note
The following commands are generally run from the CLI, you dont need the Openstack CLI to complete these tasks just ensure you have qemu-img pakcage installed
Converting images from one format to another is generally straightforward and can be done from a single simple command
The qemu-img convert command can do conversion between multiple formats, including qcow2, qed, raw, vdi, vhd, and vmdk.
qemu-img format strings:
| Image Format | Argument to qemu-img |
|---|---|
| QCOW2 (KVM, Xen) | qcow2 |
| QED (KVM) | qed |
| raw | raw |
| VDI (VirtualBox) | vdi |
| VHD (Hyper-V) | vpc |
| VMDK (VMware) | vmdk |
Note
The main formats used in the RDC are either RAW or QCOW2
The following command example will convert a raw image file named image.img to a qcow2 image file, the -f specifies the first image format and the -O specifies the output format
The following command example will convert a vmdk image file to a raw image file
The following command example will convert a vmdk image file to a qcow2 image file
Note
The -f format flag is optional. If omitted, qemu-img will try to infer the image format.
When converting an image file with Windows, ensure the virtio driver is installed. Otherwise, you will get a blue screen when launching the image due to lack of the virtio driver. Another option is to set the image properties as below when you update the image in the Image service to avoid this issue, but it will reduce virtual machine performance significantly.