How to back up external hard drive

[seepea]

I store all of my photos on an external hard drive connected to my computer.  I back up this drive using Carbonite.  I would like to invest in a second external hard drive as a second backup for my photos.  What is the best way to back up my photos from one external hard drive to another?  I could just copy the photos over, but then how do I maintain that second backup?  Is there software you can recommend that would do that?  Or is it just a matter of copying the photo folder over again?  

[Brian]

Try Microsoft Sync Toy:

https://www.microsoft.com/en-us/download/details.aspx?id=15155

As long as your Drive Letters do not change, it should work.

 

[seepea]

Thank you!