If this image is flashed on a device it will try to automatically set up extroot on any (!) storage device plugged into the USB port (/dev/sda). Keep in mind that this will erase any inserted storage device while the router is in the initial setup phase! Unfortunately there's little that can be done at that point to ask the user for confirmation.

Why

So that e.g. customers can buy a router on their own, flash our firmware, plug in a pendrive, and manage their SIP (telephony) node from our webapp.

Status

This is more of a template than something standalone. You most probably want to customize this script here and there; search for CUSTOMIZE for places of interest.

I've extracted this from a project where OpenWRT nodes auto-provision themselves in 3 stages, but I thought it's useful enough for making it public (stage 1: extroot setup; stage 2: install packages; stage 3: a Python script for app-level sync).

At the time of writing it only supports a few ar71xx routers but it's easy to extend it.

Tested with

OpenWRT Chaos Calmer 15.05 RC1 on a TP-Link WDR4300.

Building

e.g. ./build.sh TLWDR4300

Results will be under build/OpenWrt-ImageBuilder-ar71xx_generic-for-linux-x86_64.

To see a list of available targets, run this in the ImageBuilder dir: make info.

Usage

After flashing the firmware the router will have the standard 192.168.1.1 IP address, and SSH will listen there using the keys specified in image-extras/etc/dropbear/authorized_keys.

Once connected, you can read the log with logread -f.

The autoprovision script will wait for any /dev/sda to show up, then erase it and set up a swap, an extroot, and a data filesystem, and then reboots.

In stage 2 it will need an internet connection, so you should connect to its LuCI interface to set up an Internet upstream, and then it will automatically continue installing packages, finishing the whole process, and then do a final reboot.

Troubleshooting

If the build doesn't yield a firmware file: if there's not enough space in the flash of the target device to install all the requested packages then the OpenWRT ImageBuilder silently skips that target. Remove some packages from the build and try again.