rsync archive mode; equals -rlptgoD (no -H,-A,-X) so a with r or l is superfluous
H preserves hard links, v increases verbosity of the output but does nothing to the actual function.
So rsync -Harlv is the same as rsync -Ha functionally speaking although the output will have less verbosity (which could be useful for debugging and/or logging as to what is actually happening if something fails)