NAME
	ufs_copy - fast copy utility for UFS filesystem

SYNOPSIS
	ufs_copy [-a] [-B] [-c] [-e] [-b block_factor] [-s mount_point] [-v] src dst

DESCRIPTION
	The ufs_copy copies a UFS filesystem image like dd(1).
	It doesn't copy free blocks for speed and it generates
	a sparse destination file or a compressed file for saving space.

	-a	Use asynchronous I/O for fast copy. This needs kernel support.
		Do "kldload aio" or insert "options VFS_AIO" in your
		kernel config file

	-B	Copy boot blocks too.

	-c	Compress. The destination file will be cloopfs format.

	-e	Continue on error after several retries.

	-b	Specify the amount of the data which tranfered at once.
		The size is limited to block_factor * fs_fsize.
		The default size is set to MAXPHYS.
		Note: for asynchronous I/O, don't increase this value than
		default. the transfer size lager than MAXPHYS gives poor
		performance.

	-s mount_point
		Make a snapshot file of the file system on the mount_point
		and copy it to dst. The snapshot filename is specified by
		src.

	-v	Verbose

	src	Source filesystem: a device file, a mount point,
		a snaphost file or regular file.

	dst	Destination filesystem: a device file or a refular file.

EXAMPLE
	- Make a copy
	# ufs_copy /dev/ad0h /somewhere/backup_file

	- Check size and disk usage
	# ls -l /somewhere/backup_file
	# du /somewhere/backup_file

	- Make sure the image is consistent
	# fsck_ffs /somewhere/backup_file

	- Mount/unmount backup image
	# mdconfig -a -t vnode -f /somewhere/backup_file
	# mount -r /dev/md0 /mnt
	# ls /mnt
	# umount /mnt
	# mdconfig -d -u 0

	- Restore hole image
	# ufs_copy /somewhere/backup_file /dev/ad0h

	- make snapshot and backup
	# ufs_copy -s /mnt /mnt/snapshot /somewhere/backup_file

	- make a compressed copy
	# ufs_copy -c /dev/ad0h /somewhere/backup_file.cloop

	- mount the compressed copy
	# ufs_copy -c /dev/ad0h /somewhere/backup_file.cloop
	# mdconfig -a -t vnode -f /somewhere/backup_file.cloop
	# mount -r /dev/md0.uzip /mnt

SEE ALSO
	dumpfs(8), mksnap_ffs(8)

BUGS
	Don't use this for devices which have bad sectors.
	Copying from R/W mounted filesystem would give unexpected results,
	use snapshot file instead of it.
	Copying to the raw device will overwrite everything in that device,
	take care!

AUTHOR
	Hidetoshi Shimokawa <simokawa@freebsd.org>