I'm verifying my rsync backup's integrity by running the process again with the
-n) option added. According to O'Reilly all different files would appear in the terminal output, but what confuses me is that in their example and also in my both tests rsync still reports to have written data. I have a multi-terabyte archive and for me the value was in megabytes.
The first rsync actually performs copying, while the second merely reports differences, thanks to the
-noption. If there are no differences, the output will look something like this:
receiving file list ... done wrote 16 bytes read 7478 bytes 4996.00 bytes/sec total size is 3469510 speedup is 462.97
if any files differ, their names will appear after the “receiving file list” message:
receiving file list ... done /bin/ls /usr/sbin/sshd wrote 24 bytes read 7486 bytes 5006.67 bytes/sec total size is 3469510 speedup is 461.99