virt-sparsify 命令

常用示例

说明

virt-sparsify makes virtual machine disk images sparse (thin-provisioned) by zeroing free blocks inside guest filesystems and then creating a sparse copy. This can significantly reduce the on-disk size of image files. In copying mode (the default), the input image is left unchanged and a new sparse output image is produced. The output format can be changed with --convert and compressed with --compress. In --in-place mode, the image is modified directly without needing extra disk space, at the cost of potentially recovering slightly less space.

参数

--compress

Compress the output file. Only works with qcow2 format. Incompatible with --in-place.

--in-place

Sparsify the image in-place without creating a copy. More efficient but may recover slightly less space. Incompatible with --convert, --compress, and -o.

--convert _FORMAT_

Convert the output to the specified format (qcow2, raw, vdi, vmdk, etc.). Defaults to the same format as the input.

--format _FORMAT_

Declare the format of the input disk image (raw, qcow2, etc.). Auto-detected if not specified. Should be set explicitly when processing untrusted images.

--ignore _filesystem_|_volgroup_

Do not zero free space on the named filesystem or volume group. When using --in-place, the filesystem is skipped entirely. Can be specified multiple times. Use volume group names without the `/dev/` prefix.

--zero _partition_|_logvol_

Zero the entire contents of the named partition or logical volume. All data on the device is lost, but sparsification is maximised.

--tmp _block\_device_|_directory_|prebuilt:_file_

Set the location for the temporary overlay file used during copying. The `prebuilt:` form accepts a freshly-formatted qcow2 file with the input disk as its backing file (used by oVirt).

--check-tmpdir _ignore_|_continue_|_warn_|_fail_

Control behaviour when the temporary directory has insufficient space. Default is `warn` (warn and prompt for confirmation).

-o _option_,_option_,...

Pass output options to qemu-img to fine-tune the output format. Provide all options in a single -o flag as a comma-separated list.

-q, --quiet

Disable progress bars and non-essential output.

--machine-readable=_format_

Format output for programmatic parsing, enabling structured progress and status messages.

--key _ID_:key:_KEY_|file:_file_|clevis

Supply a LUKS encryption key for the named disk, partition, or logical volume by string, filename, or Clevis network-bound decryption.

--keys-from-stdin

Read encryption passphrases from standard input instead of prompting at the terminal.

-v, --verbose

Enable verbose debug messages.

-V, --version

Display version number and exit.

-x

Enable tracing of libguestfs API calls.