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NOTE: This WalkThrough is somewhat outdated. We no longer use batman-adv. The instructions for flashing nodes are still fine for e.g. Ubiquiti devices but not the TP-Link devices we use as home nodes. We hope to update this walkthrough soon.

This a walkthrough for flashing a node with an OpenWRT firmware and getting mesh-relevant packages installed. The walkthrough assumes you're using linux and that you have knowledge of the terminal. The basic idea of getting a node (router) on the mesh consists of flashing (copying files to flash memory) an operating system to the node and installing additional drivers and packages. We use OpenWRT as the operating system on our embedded devices (routers), then connect to the node (via SSH), install the related software and configure it. This operating system is meant to fit on a small amount (4MB) of flash memory.

To build an OpenWRT image from scratch, visit this How To: Mesh/Build An OpenWRT Image

Build Environment

The directions that follow assume you are runing a linux distro. Windows environments, see the instructions at the bottom of the page.

Install TFTP

verify that you have TFTP installed

   sudo apt-get update
   sudo apt-get install tftp

Mac Users will already have TFTP installed.

Download the correct firmware

For the supported routers, please find the latest firmware here:

Installing OpenWRT

There are four methods of flashing a router.

Notes on choosing a router: Mesh/Choosing_A_Router

Tested and working on:

   *Bullet M5
   *Bullet 2 HP
   *Picostation 2 HP 

Step One: Reset the router


 - Turn off the device
 - Press the reset button (near the ethernet port)
 - Turn on the device (by plugging in the ethernet w/ POE)
 - Release the reset button after the lights blink red and orange. (the router will continue blinking until its flashed)
 - Ping If it works, you're ready to upload an image. 


 - Press and hold the reset button while plugging in the powered ethernet cable. 
 - Keep holding the reset button. Look at the LED above the power LED. 
 - It will go from one green light, to two, the start flashing orange and red
 - Release the reset button when it turns on the second time.

The Bullet will now be running a TFTP server

Step Two: Configure your IP address

  • Ensure that you have an IP address different from and different from in the 192.168.1.x range.
  • You probably want to stop network-manager (not all distros use this, but Ubuntu does):
    sudo /etc/init.d/network-manager stop
  • On most linux machines (assuming your ethernet interface is eth0) setting your ip address looks like this:
    sudo ifconfig eth0 netmask up

Step Three: Install OpenWRT on the router

  • Then do the following:
    $ tftp
    tftp> binary
    tftp> rexmt 1
    tftp> timeout 60
    tftp> trace
    tftp> put <FIRMWARE>.bin

The <FIRMWARE>.bin is the name of the firmware file you want to flash.

We are hosting custom firmwares for the supported routers here make sure you download the correct firmware for your model of router.

You will see a bunch of lines like this:

sent DATA <block=13468, 512 bytes> received ACK <block=13468>

Once those lines stop coming, the router will take somewhere between 1 and 7 minutes to stop flashing its lights at you. DO NOT unplug or turn off the router until the bottom two green LEDs are solid for a minute. On the older routers the upgrade can take much longer than on the newer routers so be patient.

If you have a PicoStation running AirOS, you can use the following shell script to reflash it without needing to press the reset button:

#!/bin/sh -e
curl http://ubnt:ubnt@
curl -F fwfile=@"$FIRMWARE" http://ubnt:ubnt@
curl -F 'nil=nil' http://ubnt:ubnt@
echo "FLASHING IN PROGRESS - It will be complete when the system displays two solid green lights for ten seconds."

Note, that if you're flashing AirOS instead, at least the Bullet M5 series will remember setting between firmware upgrades and others may do so too. To reset username / password / ip address and other settings to factory default, first let the router boot, then press and hold the reset button until more lights come on and release. Wait for the factory reset to complete (a minute or two) and try to access in a browser (ensure that your own IP is in the 192.168.1.x range). Note: This procedure seems to have no effect on the Bullet 2 HP, but works on the Bullet M5. It could be that the Bullet 2 HP does not persist settings across firmware upgrades, and so doesn't have the factory reset procedure. When flashing AirOS on the PicoStation, only one green light will be on when the flash is complete.

Windows Instructions

from the directory where you stored the .bin file:

>tftp -i PUT openwrt-atheros-ubnt2-squashfs.bin

Downloads within a minute, wait about 5 minutes to finish installing...

Installing BATMAN

For Bullet, first run the following commands to free up space:

 ssh root@
 opkg remove --force-removal-of-dependent-packages remove luci*


Use these instructions if your router is connected to the internet:

 ssh root@
 opkg update
 opkg install kmod-batman-adv

Manually / Offline

If your router does not have internet connectivity when installing, then use these instructions.

Download these packages from:<openwrt_version_name>/<openwrt_version_number>/<chipset_name>/<type>/packages

As of 7/31/13, download this:

and this:

Go to and browse to the correct directory. If there are multiple types, you probably want the 'generic' one, but check with the OpenWRT wiki page for your device to make sure.

These are the required packages:


Use scp to copy them to the router:

scp kmod-*.ipk root@

Then ssh into the router and install them:

ssh root@
opkg install kmod-*.ipk

Configuring BATMAN

These notes are valid for OpenWrt 12.09 (Attitude Adjustment), which uses BATMAN 2012.4.0. In newer versions, the version of BATMAN used is 2013.0.0 and the syntax for configuring BATMAN differs slightly. See this page on for more info.

Step One: Wireless Configuration

In /etc/config/wireless:

config wifi-device 'radio0'
	option type 'mac80211'
	option hwmode '11g'
	option channel '3'        # You may want another channel
	option disabled '0'
	option phy 'phy0'

# the interface where non-mesh nodes connect
config wifi-iface
	option device 'radio0'
	option ifname 'ap0'
	option encryption 'none'
	option network 'lan'
	option mode 'ap'
	option ssid 'sudomesh'   # You should change the ssid to be unique for dev purposes

# the mesh interface
config wifi-iface
	option device 'radio0'
	option ifname 'adhoc0'
 	option encryption 'none'
	option network 'mesh'
	option mode 'adhoc'
	option bssid 'CA:FE:C0:DE:F0:0D' # You should change this to be unique for development purposes, but for meshing this should be the same for all routers on the mesh
	option ssid 'sudomesh-backchannel' # You should change the ssid to be unique for development purposes, but for meshing this should be the same for all routers on the mesh

Step Two: Network Configuration

In /etc/config/network:

config interface 'loopback'
	option ifname 'lo'
	option proto 'static'
	option ipaddr ''
	option netmask ''

# set up ethernet bridging between eth0 and bat0
# this means that packets can move between the ethernet port
# and the wifi mesh
config interface 'lan'
	option type 'bridge'
	option proto 'static'
	option ipaddr '' # this should be a unique IP
	option netmask ''
	option dns ''
	option gateway '' # an internet gateway, not sure how to deal with multiple gateways yet
	option ifname 'eth0 bat0'

# the mesh interface
config interface 'mesh'
	option ifname 'adhoc0'
	option proto 'none'
	option mtu '1528'

Step Three: BATMAN Configuration

In /etc/config/batman-adv:

config mesh 'bat0'
	option interfaces 'adhoc0' # the interface for which to enable batman0
	option 'aggregated_ogms' # no idea what this means
	option 'ap_isolation' # no idea what this means

Step Four: System Configuration

In /etc/config/system you can set hostname and timezone. This is not strictly necessary for BATMAN to work, but it should be set correctly. The below timezone is correct for the Pacific U.S. timezone (PST). The naming convention for hostnames is: <router-model-name>-<some-unique-name-you-choose>

config system
	option hostname	tl-wr703n-foo
	option timezone	PST8PDT,M3.2.0,M11.1.0

You may also have to turn off dnsmasq. (someone else can chime in if this contradicts their working knowledge)

/etc/init.d/dnsmasq disable

Step Five: Testing

You should see the 'sudomesh' and 'sudomesh-backchannel' wifi interfaces when running `sudo iwlist wlan0 scan`