Before transferring a website from one server to another, I checked disk space of website using df -h command and it says website is 84GB in size. Furthermore, du -sh /home/username/ showing 76GB but du -sh /home/username/* is showing only 5GB, where are the remaining 71GB website contents?
Solution :-
There are two possible solutions for this, let's discuss them :-
1) There must be hidden files/folders under your /home/username/ directory which you can check by below command - du -sch .[!.]* * |sort -h
2) There might be the case that files/folder present outside home directory at other locations of the server with username ownership, you can check those files/folders under backup directory or another partition like /home2.
