i'm new to linux; wanted to find out how large root is without home directory (to see if it's too large to back up to cloud). from looking around it seems i'd do "sudo du ./ [but how to get a size summary excluding the home folder?]
If your / and /home directories are mounted separately you will get respective sizes in a single command:
But if / and /home are mounted on one and the same partition you will need to get /home total and deduct it from the total of /.
and for the home you will get it by
the total size here you deduct from the size of the root above df, what remains thus is the size of the rest of root directories /* less /home.
Hope that helps.