System Recovery 2013 - What happens if my backup drive fails?

Hi,

  I've recently installed a trial of Symantec Backup System Recovery 2013 on my server and have a question.

I've setup a local backup to a USB removable HDD, and setup an offsite copy. Can someone tell me what would happen if my local USB removable HDD or offsite copy fails? I wonder how the product would deal with this?

If offsite copy drive fails then will Symantec catch up copying the data to a new one from the local USB removable HDD, and how intense would this be on resources?

And if the local USB removable HDD failed then what would happen upon installing a new one? I am a bit concerned about the restore points and how it would get itself back in sync with the offsite copy.

Many thanks

Jon