Brief
- Normal use: rsync -av <FROM> <TO>
- Ignore modify date and size, just consider checksum: -c
- Explain update motivation: -i
- Dry run, don’t update anything: -n
Examples
rsync -avnic <SRC> <DST>|grep -e ^\> -e ^\<
Report file changing just by checksum (modified times and size could be equals, it ignores them)