How does RSYNC "verify" integrity of a backup???

TeknoJnky wrote:
I have no way to verify if it did or didn't work, but putting --checksum in the rsync exclusion fields didn't cause any errors and in theory would be passed along to the backup job command line

I no files which only differs by a couple of bits, but gave this a test run with a Share that has approx 1.5GB of data (unchanged between source (NAS) and backup target (USB HDD) )

Main difference I see is between the "sent xxxxx bytes" figure
with "--checksum" : 113875
without "checksum" : 113859

Does this tell one way or another if adding the "--checksum" into the "Add files and directories to be excluded as a comma separated list" field (of the backup's Rsync settings) works ?

-------------------------------------------------------------------------------- WITH --CHECKSUM INCREMENTAL Backup started. Sat Sep 24 10:34:25 PDT 2011 Job: 001 Protocol: rsync Source: [Datatest]/ Destination: 192.168.0.200::USB_HDD_1/backups/Datatest sending incremental file list sent 113875 bytes received 246 bytes 228242.00 bytes/sec total size is 1529466744 speedup is 13402.15 Backup finished. Sat Sep 24 10:34:25 PDT 2011 -------------------------------------------------------------------------------- WITHOUT --CHECKSUM INCREMENTAL Backup started. Sat Sep 24 10:33:42 PDT 2011 Job: 001 Protocol: rsync Source: [Datatest]/ Destination: 192.168.0.200::USB_HDD_1/backups/Datatest sending incremental file list sent 113859 bytes received 246 bytes 228210.00 bytes/sec total size is 1529466744 speedup is 13404.03 Backup finished. Sat Sep 24 10:33:42 PDT 2011