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The efficient way to solving your problem

The most efficient way to solving your problem, both for you and for the DD-WRT community, is the following:

First, read through the Wiki. Allthough these pages are constantly under development, they contain a wealth of information. In many cases, your answer is already here.

If the solution you need is not in the wiki, head on to the forum.

Stop - don't immediately post a new topic. As many, many questions have already been asked and answerred, the forum contains a wealth of information as well. Yes, I may be a little harder to dig up the topic where your problem was treated, but the digging you will do will have a benefit too: you will come accross a lot of useful information on the way.

So, start by doing an extensive search on the forum, using various key words that may lead to the topics that can help you. This will save everyone a lot of time.

If all the above has not yielded any result, or has left you with more questions, or has only partially helped you - don't hesitate to open a new topic and ask for help, which will be gladly given by the community. Usually, you will have your answer in no time at all.

However, please make sure that you post at least following information to allow the friendly people on the forums to help you:

  • what device you are using exactly (brand, type, revision);
  • the exact DD-WRT version used (version number, build date);
  • a short description of what you were trying to do;
  • a short report of what happened;
  • background information (i.e. network setup, wireless setup,...) if applicable.

There is also an archived general English WRT54G/GS discussion forum and the DD-WRT discussion forum in English (this is where the action was before) and German. The old forum is where, at the moment, the most information can be found.

Common Problems and Questions

Before trying to fix any error, always make sure that you use the latest (stable) version of DD-WRT. Currently, this may be either DD-WRT v23 SP1 stable or DD-WRT v23 SP1 30-05-2006, which is featuring the new version of DNSMasq and is therefore more mature than the official stable release. The latter version can (confusingly) be found in the "unstable" section of the download area - don't worry, it is stable nontheless.

Also, never forget to clear your nvram (reset your router to factory defaults) before AND after flashing a firmware. After that, re-input your settings manually.

After all this, here are the solutions to some common problems:

Router Slowdown

TX-Errors

  • You see many TX-errors for WLAN (wireless) on your status page.
    • Set ACK timing to 0 (from the default value of 20000).
    • Other things that may contribute to a lower error rate:
  1. Set beacon interval lower than the default of 100 (75, for example).
  2. Don't use an ouput power that is higher than you strictly need, it will only produce more noise (not more signal). 75-125mW should be enough for any normal environment.
  3. Use a better antenna that the stock antenna your device comes with. This actually helps you more than increasing ouput power (as this option increases both ouput and sensitivity at the same time),
  4. Use a better antenna on your clients as well.

DHCP

  • Unable to get DHCP address from WAN.
    • Some ISPs have a MAC address registered for service on their end. Since these ISPs usually assign only one dynamic address at a time, you may need to release the IP assigned to the old router/computer to allow the DD-WRT router to get a new one. You have a few options:
  1. Clone the MAC address from the old router/computer, and leave it that way.
  2. Clone the MAC address from the old router/computer, click the DHCP Release button on the bottom of the Status->Router page. Then turn off the MAC cloning.
  3. Simply unplug the router and cable modem and plug them back in. Note: Make sure to plug in the cable modem first and wait until it is online before plugging in your router.
  4. Use the reset button on your router. (v23sp1 after upgrade from stock Linksys WRT54G v1.1)
  • After upgrading from a pre-v23SP1 to v23SP1, or later, login to web interface no longer works.
    • As of v23 SP1, the default login for the web interface is:
Username: root
Password: admin
    • If this does not work, try following the steps at the end of this entry

DHCP and DNS with DNSMasq

  • Why computers always get "192.168.1.1" for DNS.

By default all DNS requests are handled by DNSMasq (192.168.1.1). DNSMasq then forwards the requests to the proper DNS servers and caches the results. You can disable this behavior by disabling "Use DNSMasq for DNS" in the Basic Setup page.

  • Why DHCP-served IP addresses do not begin at "192.168.1.100".

DNSMasq does not give sequentially ordered IP addresses. The addresses are calculated based on your computer's MAC address and "a variable." This is normal and your computers will still get an address within the range you defined. It's just a little different from the way the original Linksys firmware worked. You can disable this behavior by disabling "Use DNSMasq for DHCP" in the Basic Setup page (although it is not recommended).

For those who want the details, it's calculated using something like [lease_start + [[mac_hash + variable] % lease_max]]. The "variable" changes whenever Dnsmasq sees a conflict.

  • Why are computers not in the DHCP lease table even though they are "connected."

The lease table is cleared when the router is upgraded, unplugged, rebooted, and in situations where a config change requires a reboot. If your computer is already connected when this happens, it will remain connected but will not be in the lease table until the next time it tries to renew. You can disable this by enabling "Use NVRAM for client lease DB" on the Services page. This will store the lease database in the NVRAM.

Troubleshooting

Debricking Asus WL-500G Deluxe after unsuccesfull DD-WRT flash or Corrupted NVRAM.

This guide applies ONLY when WL-500G Deluxe does NOT respond to the normal ASUS firmware restoration tool! (See your Driver CD for the utility)


Step 1: Download http://wl500g.dyndns.org/wl500g-clear-nvram.trx this restoration firmware was made by OLEG from http://www.wl500g.info . Rename it to nvram.trx!

Step 2: Download latest firmware from asus.com, rename it rom.trx

Step 3: Open your router by taking off the rubber nobs on the bottom, then unscrew the 4 screws.

Step 4: Configure your NIC with the IP 192.168.1.2 make sure that it is in 10MB half duplex mode!

Step 5: Look for a small chip called 29lv320 and shor PIN 10 with the golden wireless plug using a paperclip. The router will show the powerlight blinking and one of your LAN interfaces should come active. Sometimes shorting PIN 9 and 10 at the same time helps..

Step 6: Ping 192.168.1.1 If no response go to step 5 and try again.

Step 7: Open the commandshell of windows and type: tftp -i 192.168.1.1 PUT nvram.trx, and wait 5 min. Reboot your router and do step 5 again.

Step 8: Open command shell and type: tftp -i 192.168.1.1 PUT rom.trx, and wait 5 min. Reboot your router, it should show you Power, Air and connected LAN interface.

Step 9: Praise the lord, and pass the ammonition. You just did an emergency flash recovery of your WL-500G DELUXE.

Guide by Thomas Motshagen

Different Wireless Modes

Many new users are confused by the different wireless modes. This section is not meant to cover each mode entirely, but rather to give a quick overview of each mode. To understand this section, it may be helpful to know that the default router configuration (with DD-WRT or original firmware) has three seperate interfaces. WAN (Wide Area Network) is usually used for the Internet connection. The second interface is the switch (the four wired ports), usually referred to as LAN (Local Area Network). The wireless portion of your router is the third interface, usually referred to as WLAN (Wireless Local Area Network), or AP (Access Point).

  • Accessing the Wireless Modes

To access the wireless mode, log into the router, go to "Wireless" > "Basic Settings". The wireless mode can be changed using the the top-most drop-down menu. To disable the wireless portion of your router entirely use the second drop-down menu labeled "Wireless Network Mode".

Access Point is probably the most common and most popular mode. It is also the default mode. The Access Point mode allows wireless clients to access the Internet, access each other wirelessly, or access other computers that may be connected to the switch with wires. A router in Access Point mode cannot connect wirelessly to other routers, but it can have other routers connected to it wirelessly as clients or repeaters.

Client mode allows the router to connect to other access points as a client, making your router behave much like your wireless adapter in your notebook or desktop computer. In this mode, the router will no longer function as an Access Point (doesn't allow clients), therefore, you will need wires to use the router and to configure it. The router won't even be visible to your wireless configuration software or Wi-Fi sniffer software such as Netstumbler, since it no longer broadcasts beacons. In Client mode, the WLAN and the LAN will be on two different subnets.

Client Bridge mode is much like Client mode except the WLAN and the LAN are on the same subnet. This reduces the need to configure NAT and it also allows all services (such as DHCP) that are running on the original network to exist seamlessly on the bridged network. Just like Client mode, a router in Client Bridge mode will not accept client computers and it will not broadcast beacons.

  • Adhoc

Adhoc mode allows the router to connect to other wireless devices that are also available for adhoc connections. Think of this mode as a Client Mode that doesn't connect to infrastructure networks but rather connects to other adhoc-configured devices. (Think of an adhoc network as a bunch of 8 year-olds without any adult supervision. Adhoc networks lack the central management that is typical of an infrastructure type network.)

IRC

This is the shortest way to contact the developers when there is serious trouble. Before bothering them, please check any other means of solving your problem as listed on this page.

Bugtracker

Sometimes a problem you have may have already been identified as a bug. Check the bugtracker (registration required) if this is the case and provide input if neccessary.