하드디스크 백업

lsblk
fdisk -l /dev/sdc

# lsblk
NAME          MAJ:MIN RM   SIZE RO TYPE  MOUNTPOINT
...
sdc              8:32   0  74.5G  0 disk
├─sdc1          8:33   0  73.2G  0 part
├─sdc2          8:34   0     1K  0 part
└─sdc5          8:37   0   1.3G  0 part


# fdisk -l /dev/sdc
Disk /dev/sdc: 74.5 GiB, 80026361856 bytes, 156301488 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x000e6f33

Device     Boot     Start       End   Sectors  Size Id Type
/dev/sdc1  *           63 153501074 153501012 73.2G 83 Linux
/dev/sdc2       153501075 156296384   2795310  1.3G  5 Extended
/dev/sdc5       153501138 156296384   2795247  1.3G 82 Linux swap / Solaris

mount /dev/sdc1 /mnt
dd if=/dev/zero bs=4M | pv | dd of=/mnt/tmpzero.txt bs=4M
sync
rm /mnt/tmpzero.txt
sync
umount /mnt

# mount /dev/sdc1 /mnt

# dd if=/dev/zero bs=4M | pv | dd of=/mnt/tmpzero.txt bs=4M.
34.9GiB 0:14:03 [31.1MiB/s] [    <=>    ]
dd: error writing '/mnt/tmpzero.txt': No space left on device                                                    ]
0+403467 records in
0+403466 records out
50254086144 bytes (50 GB, 47 GiB) copied, 1385.26 s, 36.3 MB/s

# sync

# rm /mnt/tmpzero.txt

# sync

# umount /mnt

dd if=/dev/sdc bs=32M | pv | dd of=sdc.raw bs=512 conv=sparse

# dd if=/dev/sdc bs=32M | pv | dd of=sdc.raw bs=512 conv=sparse
10.4GiB 0:03:29 [39.0MiB/s] [    <=>    ]

qemu-img convert -O qcow2 -S 512 sdc.raw sdc.qcow2