Buffalo WHR-G125

This device is NOT RECOMMENDED for future use with OpenWrt due to low flash/ram.
DO NOT BUY DEVICES WITH 4MB FLASH / 32MB RAM if you intend to flash an up-to-date and secure OpenWrt version onto it! See 4/32 warning for details.

1) This device does not have sufficient resources (flash and/or RAM) to provide secure and reliable operation.
This means that even setting a password or changing simple network settings might not be possible any more, rendering the device effectively useless. See OpenWrt on 4/32 devices what you can do now.

2) OpenWrt support for this device has ended in 2022.
19.07.10 was the last official build for 4/32 devices.

The WHR-G125 is a 802.11g wireless router with a 5 port programmable ethernet switch.

Version/Model S/N OpenWrt Version Supported Model Specific Notes
v1.0 ? 8.09 Has unpopulated Hirose U.FL connector inside
CPU Ram Flash Network USB Serial JTag
Broadcom BCM3302 V2.9 @ 240MHz 16MB 4MB 4 x 1 No Yes Yes

OpenWrt should be installed via TFTP, follow the instructions in the HOWTO section. The correct image for this device is openwrt-brcm-2.4-squashfs.trx .

This device is supported by sysupgrade.

LuCI Web Upgrade Process

  • Browse to LuCI Upgrade URL
  • Upload TRX file to LuCI
  • Wait for reboot

Terminal Upgrade Process

  • Login as root via SSH on
  • Use the following commands to upgrade.
cd /tmp/
wget http://downloads.openwrt.org/latest/brcm-2.4/openwrt-brcm-2.4-squashfs.trx
sysupgrade openwrt-brcm-2.4-squashfs.trx
Architecture MIPS (low endian)
Vendor Broadcom
Bootloader CFE 1.0.37-1.18
System-On-Chip Broadcom BCM5354 rev 1
CPU Speed 240 Mhz
Flash-Chip Spansion S29AL032D90TFI04
Flash size 4 MiB
RAM 16 MiB
Wireless Broadcom BCM4318 802.11b/g (integrated)
Ethernet Broadcom BCM47xx 10/100BaseT Ethernet / RoboSwitch
Serial Yes
Front: Back:

Note: This will void your warranty!

  • Remove the Torx screw under the bottom label
  • Gently tear off the bottom cover

Main PCB

FIXME Pin layout unknown yet

The board has an unpopulated 12-pin Broadcom style JTAG port (JP2).

nTRST 1 2 dead TDI 3 4 dead TDO 5 6 dead TMS 7 8 dead TCK 9 10 dead nSRST 11 12 GND

How to connect to JTAG interface, and how to reflash the device with JTAG tools

See port.jtag for more JTAG details.

The default network configuration is:

Interface Name Description Default configuration
br-lan LAN & WiFi
vlan0 (eth0.0) LAN ports (1 to 4) None
vlan1 (eth0.1) WAN port DHCP
wl0 WiFi Disabled

Numbers 0-3 are Ports 1-4 as labeled on the unit, number 4 is the Internet (WAN) on the unit, 5 is the internal connection to the router itself.

Port Switch port
Internet (WAN) 4
LAN 1 0
LAN 2 1
LAN 3 2
LAN 4 3

:!: In OpenWrt versions up to Backfire 10.03, the first LAN port and WAN are reversed after flashing!

To fix the port assignment, apply the following configuration changes:

root@OpenWrt:~# uci set network.eth0_0.ports='0 1 2 3 5' root@OpenWrt:~# uci set network.eth0_1.ports='4 5' root@OpenWrt:~# uci commit network root@OpenWrt:~# reboot

If you forgot your password, broken one of the startup scripts, firewalled yourself or corrupted the JFFS2 partition, you can get back in by using OpenWrt's failsafe mode. →failsafe_and_factory_reset

Buffalo WHR-G125-specific

  • Unplug the router's power cord.
  • Connect the router's LAN1 port directly to your PC.
  • Configure your PC with a static IP address between and E. g. (gateway and DNS is not required).
  • Plug the power on and wait for the DMZ LED to light up.
  • While the DMZ LED is on immediately press any button (Reset and Secure Easy Setup will work) a few times .
  • If done right the DMZ LED will quickly flash 3 times every second.
  • You should be able to telnet to the router at now (no username and password)

The Bufalo WHR-G125 has two buttons and one switch to toggle router and bridge mode when using the vendor firmware. These buttons can be used with hotplug events.

Router (switch) bridge
Reset reset
AOSS (AirStation One-Touch Secure System™) ses
This website uses cookies. By using the website, you agree with storing cookies on your computer. Also you acknowledge that you have read and understand our Privacy Policy. If you do not agree leave the website.More information about cookies
  • Last modified: 2019/08/19 17:07
  • by tmomas