Command parameters:
is a disk image filename
is the destination format
Parameters to snapshot subcommand:
Command description:
If the option backing_file is specified, then the image will record only the differences from backing_file. No size needs to be specified in this case. backing_file will never be modified unless you use the "commit" monitor command (or qemu-img commit).
The size can also be specified using the size option with "-o", it doesn't need to be specified separately in this case.
Only the formats "qcow" and "qcow2" support compression. The compression is read-only. It means that if a compressed sector is rewritten, then it is rewritten as uncompressed data.
Image conversion is also useful to get smaller image when using a growable format such as "qcow" or "cow": the empty sectors are detected and suppressed from the destination image.
You can use the backing_file option to force the output image to be created as a copy on write image of the specified base image; the backing_file should have the same content as the input's base image, however the path, image format, etc may differ.
Supported image file formats:
Supported options:
Encryption uses the AES format which is very secure (128 bit keys). Use a long password (16 characters) to get maximum protection.
Supported options:
Supported options: