Not sure of the core reason here but perhaps a network problem causes an unhandled exception that allows rsync to think the older file should overwrite the newer file.
My OS is Ubuntu 13.10
command used is the same as in the man page.
rsync -avz src dest
Most of the time seemed to work fine, just occasionally not.
Unfortunately the "occasionally not" wiped a couple of days of email.
It is supposed to do that unless you supply --update.
Oh, also, don't -z unless rsync is networking.
As noted earlier, the cited command should just copy everything, as it did.
Of course. For some reason I thought -a included -u behaviour.
Perhaps suggest adding -u to the example on the man page? I know it isn't wrong, but may be more what people want to do?
"....ing commands copies the files in the same way, including their setting
of the attributes of /dest/foo:
rsync -av /src/foo /dest
rsync -av /src/foo/ /dest/foo "
I know the -z doesn't do anything in filesystem to filesystem.