Notes
How to fix “Cannot connect to 127.0.0.1 port 30005”
Most likely it’s a premission issue. Install rtl-sdr.rules udev files file.
$ wget https://osmocom.org/projects/rtl-sdr/repository/revisions/master/raw/rtl-sdr.rules
$ sudo mv rtl-sdr.rules /etc/udev/rules.d/rtl-sdr.rules