This page explains the general sequence needed to get OpenWrt up and running. Generally, you have two options: Flash OpenWrt onto the router's non-volatile memory, or boot OpenWrt over the network (a.k.a. "netboot"). Netbooting is not supported by all devices and/or boot loaders.

Compatibility with your router should be determined before installing OpenWrt. The Table Of Hardware page contains a list of supported devices. Certain models have links to additional technical and setup information.

OpenWrt's Version History page lists current and past releases of the firmware. A link is provided to the download page for the latest stable firmware version. Each firmware version is listed on the page, and has a corresponding link to a summary of newly-added hardware, as well as notable changes.

OpenWrt firmware files are shipped as either trx or bin files. The bin file is nothing more than a trx file with additional information added to make it compatible with the vendor's upgrade utilities. bin files should only be used when you cannot use the trx files directly.

• openwrt-brcm-2.4-.trx
  • This is the firmware in raw format, exactly as it will be written to the flash. This format is used when upgrading from within OpenWrt or during the initial install on one of the following:
• openwrt-wrt54g-.bin; openwrt-wrt54gs-.bin; openwrt-wrt54gs_v4-.bin; openwrt-wrtsl54gs-.bin
  • This is the exact same as the trx file above, with one exception – a small header has been added to the start of the file, marking it as a valid upgrade for Linksys models. Supported models:
    • openwrt-wrt54g-.bin
      • Linksys WRT54G (v1.0, v1.1, v2.0, v2.2, v3.0, v4.0)
      • Linksys WRT54GL
    • openwrt-wrt54gs-.bin
      • Linksys WRT54GS (v1.0, v1.1, v2.0, v3.0)
    • openety-wrt54g3g-.bin
      • Linksys WRT54G3G
    • openwrt-wrt54gs_v4-.bin
      • Linksys WRT54GS (v4.0)
    • openwrt-wrtsl54gs-.bin
      • Linksys WRTSL54GS
    • openwrt-wa840g-.bin; openwrt-we800g-.bin; openwrt-wr850g-.bin
      • This is also a trx file, but with a Motorola header added to the start of the file, making it a valid firmware file for a Motorola device.

There are 3 trx files, found in the micro, pptp, and bin directories explained above. Size restrictions aside, it doesn't matter which directory you pick, although if your device only has 2M of flash you will need to use micro.

It is strongly recommended that once the firmware image has been downloaded, it be checked for possible corruption with an MD5 utility. This can be verified by comparing the md5sum from your downloaded image with the md5sum listed in the md5sums file found in the download directory. For Win32 platforms, use md5sums.exe. For GNU/Linux systems, use the

md5sum

(…)

There are multiple ways to reflash the firmware; we will explain each method below. You can use any method; the end result will be the same. After reflashing, the device will automatically reboot into the new firmware.

If you are not happy with OpenWrt, you can always reinstall your original firmware. Please be sure you have it downloaded and saved on your PC.

/!\ It is strongly recommended to print a copy of troubleshooting in case you have any trouble with the install

This is the easiest method. Open your web browser, and use the firmware upgrade page on your device to upload the OpenWrt firmware.

You should use HTTP rather than HTTPS for the firmware upgrade.

If you're being extremely cautious or are attempting to reflash from a failed upgrade, you can use TFTP to install the firmware. This method is explained in detail on the OpenWrtViaTftp page.

/!\ Note: some models have additional requirements, please refer to the CategoryModel page for documentation specific to your router model.

If you already have the serial cable, you'll know how to do it, nevertheless… go cfe

It's not recommended to flash the kernel image via jtag, as it will take more than 2 hours, but it is possible jtag

Reflashing OpenWrt will overwrite the filesystem, erasing all previous applications and data. You are strongly urged to back up any changes you may have made to the system.

mtd -r write firmware.trx linux

For models low on memory (8MB), the firmware can be flashed directly from a web site.

/!\ Do not use this unless it is absolutely necessary. A dropped connection will result in a partially flashed router. You have been warned.

wget http://www.somesite.com/firmware.trx -O - | mtd -e linux -r write - linux

Shouldn't it be possible to drastically increase reliability by doing some netcat trick instead of going through unreliable (even remote?) websites? If so, document such a process here.

The configuring page is your next step. It explains how to set a password and secure access to OpenWrt.

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