root@ArduinoPB:~# opkg update
Downloading http://download.linino.org/dogstick/all-in-one/latest/packages/Packages.gz.
Updated list of available packages in /var/opkg-lists/barrier_breaker.
Downloading http://download.linino.org/dogstick/all-in-one/latest/packages/Packages.sig.
Signature check failed.
Remove wrong Signature file.
Correct one:
opkg update
Downloading http://downloads.arduino.cc/openwrtyun/1/packages/Packages.gz.
Updated list of available packages in /var/opkg-lists/attitude_adjustment.
Downloading http://downloads.arduino.cc/openwrtyun/1/packages/Packages.sig.
Signature check passed.