Firmware FAQ

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Revision as of 21:00, 14 October 2006 by Wayland (Talk | contribs)
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Contents

How can I tell if my router is truly bricked?

Since this question involves many variables, we do not have an article for it yet. Try a hard reset. See: Reset And Reboot.

I think I've bricked my router!

There's a lot of variables in answering this question and we don't have articles to cover all the different situations. But, for now, search the Wiki and the forums for more information, just to verify that it's truly bricked. Try a hard reset. See Reset And Reboot. Then see: Recovering from a bad flash.

Is my router supported?

If you have to ask, probably not. See Supported Devices
Linksys WRT54G v7.0 models are not supported and probably never will be.

I have a Linksys version 5 or 6 router.

We have a page in the Wiki just for you. Version 5 And 6 Router Information

What router should I buy?

In short, the Buffalo WHR G54s is the cheapest 100% compatible wireless router. For more information see Recommended Devices

Where do I download firmware?

http://www.dd-wrt.com/dd-wrtv2/downloads.php

What's the difference between the different DD-WRT versions?

See this

What Are Firmware or Factory Defaults?

DD-WRT firmware default settings (sometimes called factory defaults) are stored in nvram. For more information, see Factory Defaults.

How do I install DD-WRT firmware?

Make sure you have a compatible router. Make sure you follow all the instructions, especially the part about resetting your router before flashing and in between each additional flash. See Installation

How do I upgrade my firmware with TFTP?

Flashing with TFTP must not be seen as the standard procedure for flashing: only use it when you are specifically told to do so (for example in the specific instructions for flashing your brand or type of device). Normally, the GUI flashing method should be used; it should be perfectly adequate for any standard situation. See Installation

What's the default username and password?

Starting with v23 SP1, the default username is root and the default password is admin.

How do I access the router's settings?

If you have DD-WRT installed, your router's settings should be accessible by opening a web browser and typing http://192.168.1.1/ in the address bar. If you have changed the LAN IP address on the router, you'll need to type in the correct one instead. If your router doesn't have DD-WRT installed yet, try http://192.168.1.1/ or http://192.168.0.1/ or else consult the manufacturer's documentation. Whether you have DD-WRT installed or not, make sure your computer has an IP address in the same scheme as the router. Try pinging the router to make sure you have connectivity. Try accessing the settings using a network cable instead of accessing them wirelessly. Try clearing your browser's cache. If you've been messing with proxy settings, make sure you didn't leave some incorrect proxy settings in your browser. And last but not least, try holding the reset button in for 30 seconds. It will reset all your settings back to defaults, but it should let you back into the router. Also see the Wiki article on the Web Interface.

Why can't I access the web configuration for my router?

If you've read the previous question and it didn't help, then your router's HTTP Daemon might not be running. See "Regaining Access". The other problem that currently causes this is incorrect HTTP Redirector settings, found at "Administration" > "Hotspot". By default the HTTP Redirector is disabled. If you enabled the HTTP Redirector and you suspect you might have created a problem, see the fix on this page: HTTPRedirect

How do I clear the nvram?

See: Reset And Reboot.

How do I reset to factory defaults or firmware defaults?

See: Reset And Reboot.

How do I do a cold reboot?

See: Reset And Reboot.

How do I get the Internet to work on my router?

"After upgrading to DD-WRT, my Internet doesn't work anymore." A common problem for which there is no single common fix. Understanding networking, subnets, NAT, etc. would be in your best interests to troubleshoot this issue. For DSL users, generally PPPoE is the best option. You may need to call your Internet Service Provider (ISP) for settings that are particular to your connection. Some ISP's expect the MAC address of your modem to be communicating with their servers so you may need to use the "Clone MAC Address" feature. Make sure you use the correct username and password. For cable and satellite users, generally DHCP is the correct setting. For Comcast Cable users, be sure to disable STP. For users trying to share a dial-up connection, you'll need to read the Wiki article Sharing Dial-Up. At any rate, it's a near 99% chance that the problem is not your DD-WRT firmware, but instead your lack of understanding with networking.

I'm having lots of TX (transmit) errors.

Try setting the Ack Timing to 0. If you have the the transmit power turned up higher than 84 mW, turn it down to 84.

How high should I set the transmit power on my router?

Somewhere around 84 mW is considered to be the best setting for maximum power with minimum noise for most hardware. The Buffalo WHR-HP-G54 has a built in amp. If the amp is turned on, the radio power should not be set above 10mw. The forums have had discussions about what power level is safe, with little conclusion. Use common sense and don't set the power higher than you really need to. If you're trying to get more range, consider using a different antenna and make sure you have a clear line of sight, two of the most critical factors in your router's range.

How can I increase my wireless range?

This depends on if it's for indoor use in the same building or between buildings. Many factors affect your range. Consider getting a good antenna and try setting up your wireless devices with a clear line of sight. Best range is achieved by using one directional parabolic dish or yagi antenna and then disabling the other antenna on your router. Try increasing your router's transmit power to 84 mW. WRT has settings for frame burst and afterburner, you may increase range by turning these off. If you are mostly interested in Internet access then 802.11b has longer range and may actually give you faster speed on the Internet.


How can I increase range Indoors

Some buildings do not allow your signal to pass through very well. The usual reason for this is foil clad plasterboard. In an effort to insulate buildings and keep heat in, new plasterboard is foil clad to reflect infrared energy back into the room. However this means you effectively have huge metal sheets stopping all radio waves, so mobile phones, baby monitors, audio radios, WiFi all have problems picking up a signal. Doors and windows usually allow wireless to pass through unaffected, so positioning your antennas so the signal lines up through these openings will help. Also you need to concider if you can use a proper CAT5 cable between the points since the speed and reliablility of this is far better. If you need wireless coverage, concider using more than one Access Point but wire them with network cable rather than attempting WDS repeater mode. The WRT54G has a number of excellent 9 and 12db RPTNC antennas available on ebay.

How to increase range Outdoors

The most important thing for making your signal go far outside is HEIGHT! The higher in the building you position your radio the further it's signal will travel. Even a standard indoor unit with standard antennas can be used from 600m away! To go further you need to start using better antennas, the Access Point would work well with a 7db mounted just above roof hight, this will give you a good 600m to 1500m, it goes further in open areas and less far in built up areas. It's important to match the gain and height of your antenna to how far away you wish to recieve your signal. You may end up picking up signals that you would be better off not being able to see. Also the use of too much height with a 12db antenna would mean your signal does not reall come back to ground level for several km past where you wish to use it. The effect of this is that it seems your signal is weak and does not go very far. This is an illusion, the signal could be going way over your head. A lesser gain antenna at a lower height would yield a far stronger local signal and immunity for interferance from far away stray signals.

What negative number is better when bigger?

These numbers are actually in decebels or db and are expressed as negative numbers, so the less negative it is, the stronger it is.

Signal -> Low is good (well -10 is good, -98 is bad, mathematically -10 is higher than -98.)

Noise -> High is good (-98 is good, -10 is bad, -70 would be pretty bad in the real world)

SNR -> High is good (should be the same as difference between noice and signal, a difference of 20 would be great, a difference of 1 may just about work)

Signal Quality -> High is good (somehow like SNR but indexed to 100 with noise as base, percentage of the best theoretical available qualiry regarding to your local-noise, difficult to explain *g*)


Examples would be:

   Code:
     Signal  Noise  SNR  Signal Quality  
     -82     -98    16   14% 
    Signal - Noise = SNR 
   -82    - -98   = 16 
   Signal/Noise * SNR = Signal Quality 
   -82   / -98  * 16  = 13.4%


Typically Noise will be -92 which means you should get a connection with a Signal as low as -92. However it would be imprudent to leave a connection with a signal less than -85 (eg -90). The signal can be improved by -3db by doubling the power setting at the transmitting radio, eg 100mW increased to 200mW would better your Signal from -85 to -82. Antennas with increased gain would help, say you had the standard 3db antenna and changed it for a 12db antenna, thats a 9 db increase, so your Signal would increase from -82 to -73 which would be an excellent signal probably capable of 54Mbits associated speed. Using the term excellent in terms of running a WISP, it would probably be only 3 bars on a 5 bar signal strength meter. Don't worry if as a WISP your Signal Quality is low, like 14%, it's not really a problem, -82 is actually OK.

Links

How-To's Many Walk-Throughs for Different DD-WRT Configurations
Articles Some Articles on subjects like Wireless Modes, Router Modes, etc.
Glossary Wireless Networking Terms and Definitions along with DD-WRT Feature explanations