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I would like to copy for backup porposes a Linux user
home directory with several GBs of data and the usual configuration files. The source directory and the backup directory should exactly have the same contents. The OS is Lubuntu.
The directory contains hidden files and subdirectories. After some googling I found that
cp -r /source-directory /backup-directory
was the appropriate command.
The source directory filesystem is ext4 and the destination directory is NTFS. After the copy,
diff -qr /source-directory /backup-directory gives no output (so I suppose no differences). But
du -b or
du --apparent-size all give always different outputs for the source directory and the backup directory.
Why? Was the command wrong or is this use of