
=head1 名前

virt-make-fs - tar アーカイブまたはファイルからファイルシステムの作成

=head1 書式

 virt-make-fs [--options] input.tar output.img

 virt-make-fs [--options] input.tar.gz output.img

 virt-make-fs [--options] directory output.img

=head1 説明

Virt-make-fs is a command line tool for creating a filesystem from a tar archive or some files in a directory.  It is similar to tools like L<mkisofs(1)>, L<genisoimage(1)> and L<mksquashfs(1)>.  Unlike those tools, it can create common filesystem types like ext2/3 or NTFS, which can be useful if you want to attach these filesystems to existing virtual machines (eg. to import large amounts of read-only data to a VM).

To create blank disks, use L<virt-format(1)>.  To create complex layouts, use L<guestfish(1)>.

基本的な使用法は次のとおりです:

 virt-make-fs input output.img

where C<input> is either a directory containing files that you want to add, or a tar archive (either uncompressed tar or gzip-compressed tar); and F<output.img> is a disk image.  The input type is detected automatically. The output disk image defaults to a raw ext2 sparse image unless you specify extra flags (see L</OPTIONS> below).

=head2 ファイルシステム形式

The default filesystem type is C<ext2>.  Just about any filesystem type that libguestfs supports can be used (but I<not> read-only formats like ISO9660).  Here are some of the more common choices:

=over 4

=item I<ext3>

Note that ext3 filesystems contain a journal, typically 1-32 MB in size.  If you are not going to use the filesystem in a way that requires the journal, then this is just wasted overhead.

=item I<ntfs> または I<vfat>

Useful if exporting data to a Windows guest.

=item I<minix>

Lower overhead than C<ext2>, but certain limitations on filename length and total filesystem size.

=back

=head3 例

 virt-make-fs --type=minix input minixfs.img

=head2 TO PARTITION OR NOT TO PARTITION

Optionally virt-make-fs can add a partition table to the output disk.

Adding a partition can make the disk image more compatible with certain virtualized operating systems which don't expect to see a filesystem directly located on a block device (Linux doesn't care and will happily handle both types).

On the other hand, if you have a partition table then the output image is no longer a straight filesystem.  For example you cannot run L<fsck(8)> directly on a partitioned disk image.  (However libguestfs tools such as L<guestfish(1)> and L<virt-resize(1)> can still be used).

=head3 例

MBR パーティションを追加します:

 virt-make-fs --partition -- input disk.img

If the output disk image could be terabyte-sized or larger, it's better to use an EFI/GPT-compatible partition table:

 virt-make-fs --partition=gpt --size=+4T --format=qcow2 input disk.img

=head2 EXTRA SPACE

Unlike formats such as tar and squashfs, a filesystem does not "just fit" the files that it contains, but might have extra space.  Depending on how you are going to use the output, you might think this extra space is wasted and want to minimize it, or you might want to leave space so that more files can be added later.  Virt-make-fs defaults to minimizing the extra space, but you can use the I<--size> flag to leave space in the filesystem if you want it.

An alternative way to leave extra space but not make the output image any bigger is to use an alternative disk image format (instead of the default "raw" format).  Using I<--format=qcow2> will use the native qemu/KVM qcow2 image format (check your hypervisor supports this before using it).  This allows you to choose a large I<--size> but the extra space won't actually be allocated in the image until you try to store something in it.

Don’t forget that you can also use local commands including L<resize2fs(8)> and L<virt-resize(1)> to resize existing filesystems, or rerun virt-make-fs to build another image from scratch.

=head3 例

 virt-make-fs --format=qcow2 --size=+200M input output.img

=head1 オプション

=over 4

=item B<--help>

簡単なヘルプを表示します。

=item B<--blocksize=512>

=item B<--blocksize=4096>

This parameter sets the sector size of the output disk image.

The default is C<512> bytes.

See also L<guestfs(3)/guestfs_add_drive_opts>.

=item B<--floppy>

仮想フロッピーディスクを作成します。

今のところ、容量 (1440K)、パーティション形式 (MBR) およびファイルシステム形式 (VFAT) が事前に選択されています。将来的に、ジオメトリーを選択できるようになる可能性があります。

=item B<--size=>N

=item B<--size=+>N

=item B<-s> N

=item B<-s> B<+>N

Use the I<--size> (or I<-s>) option to choose the size of the output image.

If this option is I<not> given, then the output image will be just large enough to contain all the files, with not much wasted space.

To choose a fixed size output disk, specify an absolute number followed by b/K/M/G/T/P/E to mean bytes, Kilobytes, Megabytes, Gigabytes, Terabytes, Petabytes or Exabytes.  This must be large enough to contain all the input files, else you will get an error.

To leave extra space, specify C<+> (plus sign) and a number followed by b/K/M/G/T/P/E to mean bytes, Kilobytes, Megabytes, Gigabytes, Terabytes, Petabytes or Exabytes.  For example: I<--size=+200M> means enough space for the input files, and (approximately) an extra 200 MB free space.

Note that virt-make-fs estimates free space, and therefore will not produce filesystems containing precisely the free space requested.  (It is much more expensive and time-consuming to produce a filesystem which has precisely the desired free space).

=item B<--format=>FMT

=item B<-F> FMT

出力するディスクイメージ形式を選択します。

デフォルトは C<raw> です (スパースな raw 形式のディスクイメージ)。

=item B<--type=>FS

=item B<-t> FS

出力ファイルシステム形式を選択します。

デフォルトは C<ext2> です。

Any filesystem which is supported read-write by libguestfs can be used here.

=item B<--label=>LABEL

Set the filesystem label.

=item B<--partition>

=item B<--partition=>PARTTYPE

このフラグが指定されていると、出力ディスクイメージに MBR パーティションテーブルを追加します。

You can change the partition table type, eg. I<--partition=gpt> for large disks.

For MBR, virt-make-fs sets the partition type byte automatically.

=item B<-v>

=item B<--verbose>

デバッグ情報を有効にします。

=item B<-V>

=item B<--version>

バージョン番号を表示して、終了します。

=item B<-x>

Enable libguestfs trace.

=back

=head1 関連項目

L<guestfish(1)>, L<virt-format(1)>, L<virt-resize(1)>, L<virt-tar-in(1)>, L<mkisofs(1)>, L<genisoimage(1)>, L<mksquashfs(1)>, L<mke2fs(8)>, L<resize2fs(8)>, L<guestfs(3)>, L<http://libguestfs.org/>.

=head1 著者

Richard W.M. Jones L<http://people.redhat.com/~rjones/>

=head1 COPYRIGHT

Copyright (C) 2010-2023 Red Hat Inc.

