Nexus One USB Debugging with Ubuntu

In order to connect the Nexus one to Ubuntu via USB you need to have the file
/etc/udev/rules.d/51-android.rules
with the following line:
SUBSYSTEM=="usb", SYSFS{idVendor}=="18D1", MODE="0666"

You might have to restart Ubuntu, for the settings to take effect.

Then follow theses steps:

1. Disconnect the Nexus One.

2. cd to {android-sdk}/platform-tools

3. Shutdown the daemon with
sudo ./adb kill-server
Sometimes it is necessary to run the command twice to shutdown the server.

4. Restart the daemon with
sudo ./adb devices

5. Connect the Nexus One, make sure it is in debugging mode (Settings>Applications>Development)

6. Check that Nexus One was recognized:
sudo ./adb devices