[dd] How to backup USB disk to become a iso

[dd] How to backup USB disk to become a iso



1. Backup the disk /dev/sda to gz

dd if=/dev/sda | gzip > ~/system_drive_backup.img.gz

2. Restore gz to the disk /dev/sda

gzip -dc ~/system_drive_backup.img.gz | dd of=/dev/sda

3. See the progress 
happy   3706  6.4  0.0   3404   788 pts/0    D+   13:45   1:59 dd of=/dev/sdb
kill -SIGUSR1 3706

or every 2 second print out message
watch -n 2 kill -USR1 3706

####################################################
Q : 
dd: opening '/dev/sda': Permission denied
A : 
sudo chmod 777 /dev/sdb

Reference :

• 
  Disk Backup


• 
  將硬碟直接備份到另外一顆硬碟


• 
  dd opening /dev/sdb Permission Denied