Using dd for backup

we can use dd or gfdisk

The dd program is very useful for making copies of raw disk space. A common joke with `dd' is that is stands for data destroyer, so it should be noted that it’s a very dangerous utility.

we will use one of the partition we created from earlier posts /dev/sdb1

**lets create a file within disk than backup the disk and delete the file and restore the disk**

Mount The Disk

firstly, lets mount the disk

[s0x45ker--_(+_+)_--SysAdmin /]$ sudo mount /dev/sdb1 mnt/

Check Mount

lets check the mount

[s0x45ker--_(+_+)_--SysAdmin /]$ df -Th | grep sdb1
/dev/sdb1           ext4      240M  2.1M  222M   1% /mnt

										or

[s0x45ker--_(+_+)_--SysAdmin /]$ lsblk | grep sdb1
├─sdb1        8:17   0  256M  0 part /mnt

Create file to backup

lets create a file within the mount point

[s0x45ker--_(+_+)_--SysAdmin /mnt]$ sudo dd if=/dev/zero of=imagefile bs=1M count=230
230+0 records in
230+0 records out
241172480 bytes (241 MB, 230 MiB) copied, 0.247848 s, 973 MB/s

[s0x45ker--_(+_+)_--SysAdmin /mnt]$ ls
imagefile  lost+found

Disk backup

create backup of the disk

[s0x45ker--_(+_+)_--SysAdmin /]$ sudo dd if=/dev/sdb1 of=backup.sdb1
524288+0 records in
524288+0 records out
268435456 bytes (268 MB, 256 MiB) copied, 1.004 s, 267 MB/s

Delete File After Disk Backup

lets delete the file

s0x45ker--_(+_+)_--SysAdmin /]$ sudo rm imagefile

[s0x45ker--_(+_+)_--SysAdmin /mnt]$ ls   # imagefile no longer exists
lost+found

Restore Disk Backup

lets retsore the backup

firstly unmount the disk or it might say imagefile: cannot open imagefile' (No such file or directory)` when restored

[s0x45ker--_(+_+)_--SysAdmin /]$ cd .. ; sudo umount /mnt && ls
backup.sdb1  bin  boot  dev  etc  home  lib  lib64  media  mnt  opt  proc  root  run  sbin  srv  sys  tmp  usr  var

restore backup with following command

[s0x45ker--_(+_+)_--SysAdmin /]$ sudo dd if=backup.sdb1 of=/dev/sdb1
524288+0 records in
524288+0 records out
268435456 bytes (268 MB, 256 MiB) copied, 11.4738 s, 23.4 MB/s

View Backup File

the file hase been restored

[s0x45ker--_(+_+)_--SysAdmin /]$ sudo mount /dev/sdb1 mnt/ && cd /mnt/ ; ls
imagefile  lost+found

we have successfully backedup and restored a disk