Login to remote Ubuntu install through App ‘Putty’ using ssh using and login with the ‘root’ administrative user.

You can copy the content of a folder /source to another existing folder /dest with the command

cp -a /source/. /dest/
The -a option is an improved recursive option, that preserve all file attributes, and also preserve symlinks.

The . at end of the source path is a specific cp syntax that allow to copy all files and folders, included hidden ones.

If you first need to make a new target directory/folder, then you can use the mkdir command, like this:

mkdir /home/yourusername/newtargetdir

All this is useful if you want to re-install a MySQL server that won’t start, and making backups lessen the risk of loss of database files.

MySQL database files are stored in /var/lib/mysql.  This folder ‘should’ remain untouched when you remove or re-install the MySQL package.

It is also a good idea to make a backup of those database files.  I did so using the copy command above.