Backup with DD command
 

Hi all,

my laptop has a 320 GB hdd which is dual booted with win 7 and linux mint.If i remember i dont think i am using the entire 320 GB from the hdd,may be around some 200 GB.If i use a DD command and back it up to an external 500 GB hdd,will it back the entire 320 GB or only the data which is of 200 GB ?

I want to have a full backup of my HDD ,incase the hdd fails in laptop i can mirror it to a new hdd from the external hdd.

dd is used for copying raw data from your hard drive. In other words, dd does not care about partitions, filesystems, or anything else. So, you can theoretically copy the entire 320 gb into the new hard drive. But that still leaves the issue of partitions. For simplicity, you can use something like clonezilla which simplifies the task for you.