Backup to external drives - Changes only

Conshine

Registered User
Messages
488
I have an external drive that I back up all my photo's docs etc.
I also have a second drive to back up the back up (hard lesson learnt in the past!).
There is quite a lot of data, around 800GB.
I intend to use one of the drives on a weekly / ad-hoc basis to back up files, then on a monthly basis, copy to the second drive.
How can I back up only the differences between drive 1 and drive 2, rather than copying all?
As the laptop has limited space, I would connect both drives to the laptop and copy from one drive to the other, but copying all would probably run for days!

Is there something that can be run on the command line?
Or a *free* tool that I can use?

Any thoughts?

Thanks
 
Is there something that can be run on the command line?
Or a *free* tool that I can use?

Any thoughts?

Thanks

Which OS (operating system) are you using? On MacOS you can use the command line command "rsync" to do what you want. Windows versions exist too, but I've never tried them.
 
Hi,

If you're on windows you can use the excellent robocopy (Robust Copy). Go to a command prompt and type Robocopy and see if it is installed... If not then hit up google and get it for free.

Then you just go

Robocopy source destination /S /MIR

E.g.

Robocopy g:\ h:\ /S

And it will copy everything that has changed or is missing on the destination... really quick. If you use the /MIR (Mirror) command it will delete anything that is on the destination that is not on the source... so choose wisely.

Make a text file with your command in it and save it as backup.bat and then you can just double click it whenever you want to use it.
 
Which OS (operating system) are you using? On MacOS you can use the command line command "rsync" to do what you want. Windows versions exist too, but I've never tried them.
I can use either Win7 or Vista.
Any info on how I can run this on Windows?

http://www.aboutmyip.com/AboutMyXApp/DeltaCopy.jsp sounds like it might help.
This seems quite complicated - I thought it would be easier than this.
I will take a look.
Thanks!