new setup - need to replicate data to a second server

[Hero]

Hello community,  I have taken the plunge and so far I am super impressed. I am planning to use unraid as a 500g NAS to store backups but for insurance reasons I need to replicate the data to a second unraid on my lan in a different physical building. 
Can you please point me in the right direction to accomplish this? 
Obviously for bandwidth's sake I'd like to only replicate the changes.
Thank you in advance

[ijuarez]

Use Syncthing

or create a cron job using rsync