Script for file update on two storage location

I want to run a script for file update on two storage location.

Currently I am running a copy script from Server1 to Storage1 & 2. So if anybody put any doc file on server1 it’s automatically get copied to storage 1 and 2.Now what I want is

1.       If somebody update a Doc file on Storage 1 then it’s update same file on Storage 2 or via-versa by checking latest file time.

2.       Ignore any change If time is less than 90 second and same size.

3.       Create logs for updated docs with file name and time