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Installing DD-WRT on a router in most cases is almost as simple as installing a program onto your computer. However, doing it incorrectly can leave you with a modem that you have to throw away. Installing programs on a router, known as firmware, are achieved by a method called flashing. This article helps you determine which installation process is for you on your supported router, as well as giving router suggestions and information about flashing each one.


Choosing the Correct Firmware - Extremely Important

Is Your Router Supported?

For a list of devices working with DD-WRT, please see wiki page Supported Devices, or Hardware Database (As of fall 2009 the Hardware Database is still in Beta).

If your device is supported, you may find specific information in the Hardware-specific section for your modem. However, to avoid breaking your modem, please finish reading this entire page on Choosing the Correct Firmware first. You will then want to follow what is written for your particular device -clock.

Before You Download, Upgrade, or Flash

Before you try to take any actions, including loading any firmware to your the English Broadcom Forum Announcement entitled Peacock Thread It contains more information than just for those that having problems. Unfortunately, skipping this step leads many to brick (break) their routers.

Start there... do some research... then ask questions. Don't just load V24-Final or SP1. (Read the English Broadcom Forum Announcements referenced above to find out why). The user-friendly dd-wrt download page [[1]] will help you identify the correct "killer" and dd-wrt firmware versions (as applicable) for your device as needed. However, you must use the peacock thread and use the information in the Hardware-specific section to accurately identify your hardware and not create a problem that renders your modem useless.

After you have read THIS page, and gotten some background on the peacock page, the Hardware-specific section may be the most useful section for you in terms of identifying your modem, figuring out what files you need to download (including instructions), and figuring out the correct installation procedures.

Identifying Your DD-WRT Firmware

  • Use the brand-specific information in the Hardware-specific section to accurately identify which model you have. Start with the main brand heading (ie, "Linksys"). Use that information - instead of just going by what model you think you have - clock.
  • As the peacock thread mentions, using the incorrect file is one of the worst things you can do. Fortunately, dd-wrt has simplified this immensely with their search format. Once you have identified your modem accurately, you may be able to go straight to DD-WRT Downloads page (or secure version) and find the files you need. Again, check the Hardware-specific page for links to detailed instructions that may indicate how many files you need, etc (- clock).
  • Some newer routers are not supported by the latest stable release. Check the Supported Devices list for the minimum required DD-WRT version for your device. You may need to use an SVN or experimental build.
    • For a comparison of the builds, see File Versions.
    • Updating through the Web GUI (ie, the modem's online interface) means you need to use the _generic version.
    • Use the _mini version when upgrading from original Linksys firmware. You need the _micro version if your hardware has 2 MB of flash (WRT54G v5 through v8 for instance). Use the "_mini" firmware if your hardware has 4 MB or more of flash (WRT54GL for instance). (Again, use the download page's search function for help here - clock).
  • Read the changelog and all other information files on the download pages. They contain important information!

Downloading Your DD-WRT Firware

  • You will need to save a number of files (firmware, instruction pages for offline work, etc). Starting a folder for this project before downloading anything is advisable - clock.
  • Ensure you are using the correct version of the firmware (again, the search function on the download page above should be accurate if took appropriate action to correctly identify your modem; only download firmware from that page - clock.
  • Download the latest stable release from the DD-WRT Downloads page (or secure version).
  • Depending on your specific needs, you may need more than one download - such as a "killer" version, which must be installed prior to the dd-wrt firmware. The search function should bring up both. If instructions are provided for your modem in the Hardware-specific section, check that to see what is needed. Again, the peacock thread will give you important information on why choosing the wrong size can completely break your modem - clock).
  • If you downloaded a .zip file, then extract the archive. (If it is a .bin file, leave it alone - clock).
  • Confirm a good download by comparing the MD5 hash fingerprint of the firmware you downloaded with the published checksums. See Hashes & Checksums for further info and instructions.

"Flashing" Your Modem with dd-wrt Firmware

As mentioned, flashing is the process of replacing the existing firmware on your modem with new firmware. Some like to think of it as installing software. Although this is not entirely accurate, it gives a basic idea of what is going on - clock.

The most important aspect of this section to absorb is the precautions. People kill modems constantly by not following these advisories. Please take the time to learn and absorb them - clock.

Below, three methods of flashing will be covered: using your modem's online interface (Method 1: Flashing with Web GUI); Method 2: Flashing with TFTP; and Method 3: Flashing with Command Line. Your modem may dictate what you use. After reading this page, please see the Hardware-specific instructions to clarify what is best for your modem - clock.

If you do not already have a dd-wrt firmware version on your modem, you may have to run a "kill" firmware program on your modem first. You should be able to find this using the search function (dd-wrt download page [[2]]) for your specific device. The process of installing that firmware is probably covered in the Hardware-specific section under your device. It will be similar to simply repeating the processes outlined below for that specific "kill" file - clock. .


Follow all the instructions precisely, or you may run into trouble. Incorrectly flashing can brick your router!

  • For the initial flash from the Linksys firmware, do not use Firefox, use IE to flash the router (even OS X IE works). Once DD-WRT is running, you can use any browser you like to administer or even flash the router.
  • Do NOT use a wireless connection to upload firmware. Use a wired connection. It is recommended that you disable any wireless adapters on your system to ensure that none are used for the transfer.
  • Do NOT flash your firmware over an SSL (HTTPS) connection. Make sure you are using HTTP.
  • Disable your anti-virus-software, as a false-positive virus detection could interrupt the upload.
  • If you need to use TFTP to upload firmware, disable your software firewall first.
  • You will not have internet access through the router during the process of replacing the firmware. We recommend you save this webpage and the Recover from a Bad Flash and FAQ pages to your hard drive (use File->Save As, *NOT* a bookmark). This will allow you to review the information offline in the event that something goes wrong.
  • Do not forget to make note of your current settings, especially if you have static IP addresses. A quick way of doing this is to take screenshots of your current configuration screens.
    • It can be essential to record your current WAN MAC address. Some ISPs do not allow an immediate change of the routing hardware and changing the firmware changes the MAC address.
  • Have a secondary router or internet connection available while experimenting with your router's firmware, to expedite any trouble shooting and remove the risk of becoming stranded.
    • If you have a cable modem which connects to your router with ethernet, you can plug your PC straight into the modem should you have any problems. Your PC will be assigned your external IP with DHCP, and you will be on the net. Remember to use a software firewall.

Method 1: Flashing with Web GUI

The following instructions are very general and apply mostly to Linksys routers. Check for hardware-specific instructions in the Hardware-specific section.

  1. Reset your modem
    1. Use Hard reset or 30/30/30.
    2. While not as preferable (this may cause problems down the line) you can reset to Factory Defaults instead.
      1. If you do decide to restore defaults, if you do not know the IP address, username, or password of your router, you will need to use the reset button (this does not appear to be referring to a Hard reset or 30/30/30; this appears to be referring to a simple 30-second reset - clock). Be careful when using this method! Apparently if you have OpenWRT already on your router the reset button may not function as it is assumed here and may actually brick your router! Research the functionality of your current firmware to be safe.)
      2. Again, if you decide to restore defaults, if you already have a version of dd-wrt installed, and you know the IP address, username, or password of your router, you can use this method (other modems may require different instructions):
        • Follow the instructions in the next section to log in to the Web GUI.
        • Click the "Administration" tab.
        • Click the "Factory Defaults" sub-tab.
        • Select "Yes".
        • Click the "Save Settings" button.
        • A new page will open, click "continue".)
  2. Log on to the Web GUI (if you have not done so already).
    1. To use the Web interface, you will need to have Javascript enabled with any security restrictions disabled. Some versions of the Linksys firmware Web GUI have trouble with different browsers (some don't work with Firefox, some don't work with Safari). If the Web GUI is giving errors, try switching to a different browser.
    2. Type in the IP address of the router (typically, the default is, especially with Linksys) into the address bar of your browser. (If you do not know the router IP address, you can attempt to obtain it).
    3. You will be prompted for username and password. (If your modem already has a DD-WRT versions starting with 2006-Feb-28, the default username is root. Prior versions have a blank username by default. For Linksys firmware, the default username can be left blank or set to anything. For both DD-WRT and Linksys firmware, the default password is admin. Search online for other defaults on other modems).
  3. Upload the Firmware.
    1. WARNING:It is VERY important that you not interrupt the setup while the router is being flashed and rebooted. Do not turn off the computer, close the web browser, or turn off the router during this process! (I usually just take a step back, and turn my head away so I don't breathe on it for these crucial 2 minutes).
    2. This section is written for a dd-wrt web GUI. Your modem's GUI's operations may be different. Please see the previous comment about the possible need for "kill" firmware before your dd-wrt installation. This section may not work for your modem as written. Please see the Hardware-specific section for information on your specific modem's needs.
      1. First do a hard reset on the unit that DD-WRT is to be loaded onto.
      2. You should be in the Web GUI of the router. Go there now (as discussed above).
      3. Click the "Administration" tab
      4. Click the "Firmware Upgrade" sub-tab.
      5. (Only applicable when DD-WRT is already installed.) Choose the option to Reset to Defaults after flashing.
      6. Click the "Browse" button and select the DD-WRT .bin file you downloaded and confirmed.
      7. Click the "Upgrade" button.
      8. The router will take a few minutes to upload the file and flash the firmware. During this time, the power light will flash.
      9. A new page will open confirming that the upload was successful (Installation#Possible errors if not). Now wait about 5 minutes before clicking "Continue".
      10. Lastly, do another hard reset on the unit.
      11. If flashed successfully you will now be able to access the DD-WRT web interface at (again, that is default for most Linksys, etc modems; does not apply to all modems. Check your modem's IP before you start this process - clock).
  4. Possible Errors with Uploading Firmware
    1. [Comment added 2007/03/27 by staylor] Or, you won't be at the DD-WRT web interface I have a WRT54g v1.1 (also with WRT54gl v1.1), flashing with DD-WRT v23 sp2. I waited the requisite number of minutes, and my "Wireless-G" badge lit up (a good sign), but when I clicked "Continue" after the upload was successful, I did not get to the DD-WRT web interface. Nor was the device ping-able.
    2. [Comment added 1/04/08 by jwebste1] I can confirm Staylor's comment above for a brand new store bought WRT350N (had to soft reset the router to get the mini install to become accessible on Holding down the reset button for 30 seconds (leaving the power cable connected) re-booted the router, and all was fine thereafter. If the above doesn't result in a successful load of the DD-WRT web interface, try a "ipconfig -renew" in a command prompt window.
    3. [Comment added 12/22/09 by clock] After initially attempting the install of the "kill" file for my modem (as described in my modem's Hardware-specific section) my browser kept providing an error message. Finally, I thought the router had been bricked. A quick look at the peacock thread showed that pinging the modem and receiving a TTL of 100 meant that, which the modem appeared broken, it was ready for the installation of the dd-wrt .bin file for my modem. Using the tftp.exe discussed at the peacock and at [[3]], I was able to install the dd-wrt firmware without much more fuss.
    4. Again, the best method is to look first at your Hardware-specific guidelines and refer to those instructions, keeping in mind the Precautions outlined above.
    5. During the firmware upload process, if your router says something similar to, "Upload Failed," you may be using the wrong version of DD-WRT. This may occur through the web GUI if you use a *wrt54g.bin version when you should have selected the generic version instead. It may also be that your router requires the mini version to be flashed before the full version. Be sure to double check to make sure you have the right version (as described in the first section of this page - clock). If you are certain that your router is supported and that you have the correct firmware, you may simply need to use a different web browser (e.g. from Firefox to Internet Explorer).
    6. After clicking Upgrade when upgrading firmware from one DD-WRT version to another, if you are using Firefox there may be a problem with the upload. In this instance the screen fades to white with a countdown timer and is followed by a Connection Reset message shortly after. After this you cannot access the Web GUI again, and a router reboot will result in a flashing power light (WRT54GL is the case in point). You can recover from this and use a different browser (e.g. Internet Explorer) to upload the firmware.
    7. If logging in fails with the default username/password, you can reset the password with a Reset And Reboot.
  5. Reset Again
    1. You can use Hard reset or 30/30/30 again. Do this only after you have confirmed that the firmware upgrade is working. At this point you may have temporary problems using Web Interface, so just ping your router.
    2. Many Web Interface problems can be solved by a hard reset and by clearing your browser cache.
    3. See Reset And Reboot.

Method 2: Flashing with TFTP

Although TFTP is a safe method to flash many routers, it is not be seen as the standard procedure for flashing most devices, except if you are specifically told to do so in the specific instructions for flashing your brand or type of device (see Hardware-specific section). Normally, the GUI flashing method should be used, as it is adequate for the vast majority of standard situations, but refer to the Hardware-specific section to be sure.

Tftp is easy: if often requires one quick box uncheck and a quick click - then you are good to go. It is great for instances when web GUI malfunctions or the modem appears to be (but is not) bricked - clock.

If you still wish to flash with TFTP, see the articles TFTP flash, Asus TFTP Flash and Recovering with TFTP.

Method 3: Flashing with Command Line

This is available on routers that already have DD-WRT installed and Telnet/SSH enabled.

It's the *ONLY* recommended mode to upgrade the router wirelessly. (It may not be useful in certain, two-part firmware upgrades that require a "kill" sequence - clock).

telnet or ssh into dd-wrt Download the firmware to the router's /tmp directory with wget or scp

cd /tmp

Alternatively, you could use the mounted share if you have one, and simply download the file there.

compare the MD5 checksum of the original and the downloaded file

md5sum dd-wrt.v2x_generic.bin

Write the firmware to flash

write dd-wrt.v2x_generic.bin linux



Restore factory defaults using erase nvram command or reset button

Other Notes

Upgrading to a Newer Version of DD-WRT

If DD-WRT is already installed on your router, you can simply upgrade to a new version via the web interface or TFTP. However, it is highly recommended that you restore the router to defaults using the reset button before and after flash. Never restore old backups from previous versions! Skipping these steps could lead to a bricked device!

Please see wiki article Hard reset for further information on how to restore your device back to DD-WRT default settings.

Configuration Notes

  • You must start to configure router from scratch. Do not try to use config files from older firmware versions.
  • It is strongly advised that you do not disable the "Boot Wait" option under the "Administration" tab. Boot Wait allows you recover if you flash your router improperly.

If something goes wrong

  • If your router fails to reboot (power light doesn't stop flashing, no web interface, etc) you will need to Recover from a Bad Flash. Additional help can be found by doing a forum search.
  • The peacock thread's section on bricked modems ([4]) can help you to identify if you have a real problem or not.

The Hardware-specific section has been moved.