It is what the message tells you. You must provide an absolute path to -B/--bind rather than a relative one. Here that could be for example -B $(realpath inputdir) or -B /home/rakesh/inputdir and not just -B inputdir because the latter is relative to the current location you are in and not absolute with respect to the root dir which is /. Does that make sense to you? By the way there should be no need to sudo this.