# udev Rules for Red Hydrogen One

## Symptom

So you have your shiny new H4v-enabled Red Hydrogen in your hands, you’ve enabled USB Debugging on-device and you attach your cable… No confirmation prompt.

Firing up adb logcat you are told that you have no permissions even though the user is in the plugdev group.

## Solution

You need to add a new rule for the device.

Connect the usb cable and run dmesg. At the end, you should see something like:

[ 2356.608888] usb 7-3.4: new high-speed USB device number 6 using xhci_hcd
[ 2356.733916] usb 7-3.4: New USB device found, idVendor=2ff0, idProduct=000e
[ 2356.733918] usb 7-3.4: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[ 2356.733920] usb 7-3.4: Product: RED Hydrogen One
[ 2356.733922] usb 7-3.4: Manufacturer: RED
[ 2356.733923] usb 7-3.4: SerialNumber: xxxxxxxx


Edit the rules file. Your filename may be slightly different.

sudo nano /lib/udev/rules.d/51-android.rules (or vi or emacs or whatever you prefer)

The vendors are usually alphabetical. Add a new entry. For me, based on the above, it was:

#Red


Unplug the device, and then re-attach it. You should now be prompted to allow the connection.

If Android Studio or IntelliJ were already running, you may need to restart them.

### Caveat

What if you have a version of 51-android.rules that is being updated by a third party? You might be getting it from someone’s github repo, or maybe by going to the Android developer site and running sudo apt-get install android-tools-adb.

If you have a copy of that file that will be dynamically updated, any changes you make could get wiped out. In that case, I’d recommend having a secondary file for your own changes.

sudo nano /etc/udev/rules.d/51-android-extra.rules and enter the following:

# Skip this section below if this device is not connected by USB
SUBSYSTEM!="usb", GOTO="android_extra_usb_rules_end"

# Devices listed here in android_usb_rules_{begin...end} are connected by USB
LABEL="android_extra_usb_rules_begin"

#Red