Setting up a wireless repeater with DD-WRT and Tomato firmware

So you can’t cover your home or business with an adequate wireless signal. Here’s what you can do.

You can purchase a wireless router at local thrift stores for under $10.  When shopping for routers, look for Wireless N routers and try to find a router that supports tomato or DD-WRT.

A mixed network

I decided to put tomato on my main router and DD-WRT on my second router.

First Router Setup

The first router I setup with tomato, setting a SSID, turning on QoS and setting wireless security.


Second Router Setup

  1. Set your computer to a static IP of
  2. Connect your computer to the second router by one of the wired LAN ports.
  3. Open the address in a web browser.
  4. Click on  the Wireless -> Basic Settings tab
    • Under the Physical Interface Section, set the following
      • Wireless Mode : Repeater Bridge
      • Wireless Network Mode : Must Match Primary Router
      • Wireless Network Name(SSID) : This should match the first router exactly including exact the letter case
      • Wireless Channel : Match the first router’s channel
      • Wireless SSID Broadcast : Enable
      • Network Configuration : Bridged
      • Save

    • Under the Virtual Interfaces Section
      • Click on Add
      • Wireless Network Name(SSID) : Make this different from the first router’s.  Although you will connect to either, setting roaming under the advanced settings to aggressive on your laptop or other devices  will help your device go to the strongest signal.  (you should remember each connection)
      • Wireless SSID Broadcast : Enable
      • AP Isolation : Disable
      • Network Configuration : Bridged
      • Save
        Wireless Basic
  5. Click the Wireless -> Wireless Security tab
    • Physical Interface Section
      • Security Mode : Has to match the security on the main router- You must set the security to WPA2-AES
      • WPA Algorithms : Make it the same as the first router
      • WPA Shared Key : Make it the same as the first router
      • Key Renewal Interval (in seconds) : Leave the at the default
    • Virtual Interfaces Section (note if you don’t see this section your firmware should be atleast v24-sp2)
      • Security Mode : Must Match Physical Interface
      • WPA Algorithms : Must Match Physical Interface
      • WPA Shared Key : Must Match Physical Interface
      • Key Renewal Interval (in seconds) : Leave default
      • Save
        Wireless Security
  6. Open the Setup -> Basic Setup tab
    • Connection Type will be: Disabled
    • Set STP for Disabled (Enabled sometimes can cause connection problems)
    • IP Address : (Assuming Primary Router IP is
    • Mask :
    • Gateway: (again assuming Primary Router IP is
    • DHCP Server: Disable
    • Local DNS: (if IP of Primary Router is
    • Assign WAN Port to Switch : Optionally enable this to use the WAN port as another LAN port.
    • Save
      basic setup
  7. Log back into the router at it’s new IP address of
    • Open Setup -> Advanced Routing tab
    • Set Operating mode to “Router”
    • Save
      Adv Routing
  8. Open Services
    • Disable Dnsmasq
    • Save
  9. Open the Security -> Firewall tab
    • Uncheck all boxes…except Filter Multicast
    • Disable SPI firewall
    • APPLY Settings
  10. Reboot the router.
  11. Once you have it working, go to the wireless security tab, and set the same type of security AND key for both the primary and the repeater ssids and hit apply. Avoid WPA2 Personal MIXED, as it will likely kill communication between the routers (see Security section below for more on this). WPA2 Personal is fine.
  12. Set your wireless back to auto

The router should now be connected to the main router.   This will extend your wireless across your home.  Why?   Your router is more powerful than wireless cards and can ‘reach’ the main router.

Credit – DD-WRT wiki

Note:  This is in a lab at my home and the mac addresses and IPs have been changed.

Use SoftPerfect’s Wi-Fi Guard to keep an eye out on what is connected to your network.

Soft Perfect Wi-Fi Guard


Looking for free wireless software?  

Amped Wireless, Xirrus Wi-Fi Inspector, NetSurveyor, Acrylic Wi-Fi Scanner, Homedale, Lizard Systems and Vistumbler is the top free software to perform a basic wireless survey.

Many of these offer GPS support and allow the exporting of a survey to a KML file.  This can then be imported into Google Earth.

1 Acrylic

2 Xirrus

3 Lizard Wi-Fi Scanner

4 Netsurveyor A

4 Netsurveyor B

5 Amped Wireless Analytics

6 Homedale Portable

7 Homedale

8 Homedale

9 Homedale Location

10 Homedate options

11 Vistumbler

Wireless Surveys/Spectrum Analysis
It is important to perform a wi-fi survey so that you can determine not only the perfect place to locate your access point or bridge but to gain an understanding of the channel co-existence challenge you may face.  With wireless access points in surrounding neighborhoods and businesses, you will need to  perform a survey by walking around and mapping out the BSAs (Basic Service Area) of wireless that surrounds you and your organization.

Below is an example of our school’s perimeter.  Matt, Chris and James, students in the Computer Information Technology, class performed a survey using a Microsoft GPS and Vistumbler.  This survey revealed access points and their channels of current wireless at our institution and  includes APs in surrounding businesses and neighborhoods.  These were mapped using Google Earth after exporting their KML file from Vistumbler.

This type of survey allows IT professionals to analyze data exported to ensure the correct channels can be used at their organization.

Miller Goodroe Felts

After exporting the wireless information, you can analyze each access point or wireless device by clicking on it.  Below is an example of the information exported into Google Earth.   Each device shows SSID, Network Type, Mac Address, Channel, Security, Encryption Type, Data Rates, Latitude, Longitude and Manufacturer information.   Analyst using this information can also determine the best placement of wireless devices along with channel information.

ESSID Expanded

Channel co-existence is when access points share channels that are very close to one another.

802.11 wireless on 2.4 Ghz has three non-overlapping channels.  These channels are 1, 6 and 11.  The closer channels are, the more likely interference will take place.  With the amount of wi-fi in use today, IT professionals have to chose between 2.4 Ghz and 5 Ghz and and try to select channels that are not in use if possible.   Professional access points and bridges can also adjust power as necessary.   A dense population can make this very challenging.

If you look at the students’ survey by zooming out to see how many access points can be seen, this is what you are looking at!  Now you can see why site surveys are important at your organization.


In addition to this survey, a secondary survey using a spectrum analyzer is very important to search for interference from other sources.  (See our review of the Airview Spectrum Analyzer)


Channel information (Chart from Wikipedia)


Here’s another look at a wireless survey showing vertical lines and signal strength.

Another view James Miller KML

Netgear Used in the above repeater/bridge modification
The Netgear WNR2000v2 is an excellent router to modify if you want a router that supports DD-WRT.  Although the router has reached its end of life, you can modify the router by flashing it with DD-WRT.   How much did I pay for this router? $3 at a thrift store.

Flashing with DD-WRT

  • Flashing with DD-WRT – Link
    • You must flash with .chk file first
    • Flash of .bin file must be <4mb
    • Follow the instructions thoroughly
      • After flashing with the initial and the firmware, you can upgrade the firmware again here.

The router can also be modified with antenna wires from an old laptop screen and wireless card.





Did you brick it?  You can easily unbrick it by downloading the TFTP utility from DD-WRT and TFTPing the original firmware back on the router.   Remove the two screws at the bottom of the router and follow the steps below.

Original Netgear Firmware


TFTP utility (GUI)

About TCAT Shelbyville IT Department

The Tennessee College of Applied Technology - is one of 46 institutions in the Tennessee Board of Regents System, the seventh largest system of higher education in the nation. This system comprises six universities, fourteen community colleges, and twenty-six Applied Technology Colleges.
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