Asus RT-N66U
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- | = | + | {{Languages|Asus RT-N66U}} |
- | + | <br> | |
+ | [[Image:ASUS RT-N66U.jpg | right | 360px]] | ||
+ | __TOC__ | ||
+ | <br> | ||
+ | =Hardware [http://en.techinfodepot.shoutwiki.com/wiki/ASUS_RT-N66U Specifications]= | ||
+ | {| style="text-align:center; position:relative; " width=50% border="1" cellspacing="0" | ||
+ | !CPU | ||
+ | |Broadcom 4706 @ 600MHz | ||
+ | |- | ||
+ | !Flash/RAM | ||
+ | |32MB / 256MB | ||
+ | |- | ||
+ | !Wireless support | ||
+ | |2.4GHz and 5GHz bands | ||
+ | |- | ||
+ | !Wireless controller | ||
+ | |[http://www.broadcom.com/press/release.php?id=s474934 Broadcom BCM4331] | ||
+ | |- | ||
+ | !MIMO config | ||
+ | |3x3 (both bands) (see [https://forum.dd-wrt.com/phpBB2/viewtopic.php?t=86437&start=26 Ref: forum]) | ||
+ | |- | ||
+ | !ETH chip | ||
+ | |Broadcom BCM4706 | ||
+ | |- | ||
+ | !Switch | ||
+ | |Broadcom BCM53125 | ||
+ | |- | ||
+ | !Ports | ||
+ | |Gigabit LAN (4) and WAN (1) | ||
+ | |- | ||
+ | !USB | ||
+ | |2x USB 2.0 | ||
+ | |- | ||
+ | !Other | ||
+ | |Micro SDHC socket (internal) | ||
+ | |- | ||
+ | !Power supply | ||
+ | |DC Output, 19 V, max. 1.58 A current (=> max 30W) | ||
+ | |- | ||
+ | !Serial header | ||
+ | |8, n, 1, no flow control, 115200. | ||
+ | |} | ||
+ | <br> | ||
+ | =Installation Instructions= | ||
+ | Read the [[Firmware FAQ]], [https://www.dd-wrt.com/phpBB2/viewtopic.php?t=51486 Peacock Announcement], new build, and model-specific threads.<br> | ||
+ | '''<span style="color:#ff0000">WARNING</span>:''' This 'Dark Night' presents significant risk to bricking that requires careful adherence to the installation process, however, there is a built-in and robust Recovery Mode.<br> | ||
+ | '''NOTE:''' The NVRAM issue has been resolved in newer CFE versions (and K3X builds).<br> | ||
+ | '''NOTE:''' It is '''''highly''''' recommended to use Private, Incognito, InPrivate browsing mode with no extensions or add-ons enabled, and no passwords saved to the browser in any way when flashing or accessing the webUI. It is preferred to use a Portable browser such as Firefox, Firefox ESR, or Pale Moon. If you run into issues, clear browser cache or override with CTRL+F5<br> | ||
- | + | ===Preparation=== | |
+ | * If upgrading to DD-WRT from other firmwares, then use a '''*.trx''' file, as in '''*_RT-N66U.trx''' file for initial flash and upgrades, '''or only half the memory will be available''' (with ASUS routers, using a *.trx file is always a safe bet). | ||
+ | * If you are upgrading from one version of DD-WRT to a different (newer/older) version of DD-WRT, you can also use the firmwares that end in '''*.bin'''. as in '''_mega.bin''' or '''_big.bin''' | ||
+ | * '''<font color="red">IMPORTANT:</font> [[Asus_RT-N66U#CFE_Version_.28or_Update.29|Determine what version of CFE you have on your router]], <font color="red">if CFE v1.0.1.3 (64K nvram) or 'NEWER' - DO NOT USE K2.6 builds</font>''' | ||
+ | * If using Older CFE (32K nvram) you can use K2.6 builds | ||
+ | * Reset '''BEFORE''' and '''AFTER''' firmware upload. If upgrading from DD-WRT to a newer version of DD-WRT, then ''before'' is (mainly) optional. | ||
+ | * Refer to the [[Asus_RT-N66U#Notes|Notes]] section below if any of the following steps are confusing | ||
- | ==== | + | =====Upload via Web GUI ===== |
+ | #[[Asus_RT-N66U#WPS_button_to_Clear_NVRAM|Reset NVRAM via WPS button]] , or select WebGUI option: Factory Default settings. | ||
+ | #Upload the DD-WRT build using the stock web GUI (use file ending in .trx or .bin, according to description under [[Asus_RT-N66U#Preparation|Preparation]]). | ||
+ | #Wait until the router reboots itself, which '''can take at least 10 minutes''' (some times 30 minutes or more). Be patient and wait until you get a response from both ping and the routers WebGUI when you use your PC to access the router. | ||
+ | #[[Asus_RT-N66U#WPS_button_to_Clear_NVRAM|Reset NVRAM via WPS button]], or select WebGUI option: Factory Default settings. Wait for the router to reboot!! | ||
- | + | Note: If you are having trouble uploading a newer version of DD-WRT, using the WebGUI, then you might want to try to use a different browser. Sometimes it solves the problem. | |
- | + | =====Upload via ASUS Recovery Utility===== | |
+ | #Set your computer to a [[Static_IP|static IP]] (e.g. 192.168.1.12), subnet 255.255.255.0, default gateway 192.168.1.1 | ||
+ | #Put router into recovery mode by holding down the reset button while powering up the router, wait until the power led is blinking slowly, then release the reset button. | ||
+ | #Access the Asus CFE recovery mode by issuing 192.168.1.1 in browser field. | ||
+ | #Browse to select the DD-WRT trailed build ('''N66U big or mega .trx''') then click ''Upload''. | ||
+ | #Wait until the router reboots itself, which '''can take at least 10 minutes'''. | ||
+ | #If it doesn't reboot after 30 minutes, power off for 10 seconds, then reset via [[#WPS_button_to_Clear_NVRAM|WPS]] | ||
+ | #Reset (via WPS) or reenter recovery mode and select to ''Restore defaults NVRAM values'' | ||
+ | #*(Optional?) When it completes (should be quick), type this in the browser field then press enter: | ||
+ | #*http://192.168.1.1/do.htm?cmd=nvram+commit | ||
+ | #Wait until the router reboots itself, then access the DD-WRT GUI at 192.168.1.1 to set a password. | ||
- | + | =====Switching from Tomato===== | |
+ | #Navigate to the Tomato firmware update page | ||
+ | #*''Administration'' -> ''Upgrade'' | ||
+ | #Upload the firmware you downloaded in step 1 | ||
+ | #The router will reset several times and change its IP address to the default one (192.168.1.1). | ||
+ | #Navigate to http://192.168.1.1/Factory_Defaults.asp | ||
+ | #* The login credentials have been reset to the default dd-wrt username/password (root/admin) | ||
+ | #Set "Restore Factory Defaults" to yes and click "Apply Settings" | ||
+ | #After reboot, set a new user/password | ||
- | + | ::Note: Reset to factory defaults after flashing from Tomato to DD-WRT to avoid undesired behavior and instability. | |
- | = | + | =Upgrade to newer DD-WRT= |
- | + | * [https://www.dd-wrt.com/wiki/index.php/Asus_RT-N66U#WPS_button_to_Clear_NVRAM Clear settings (Clear NVRAM)] | |
+ | * Router should revert to default IP (192.168.1.1), so you may have to change your client's IP to the same subnet (e.g. 192.168.1.2). | ||
+ | * Use browser to navigate to 192.168.1.1 | ||
+ | * DD-WRT GUI: ''Administration'' -> ''Firmware upgrade'' | ||
+ | * [https://www.dd-wrt.com/wiki/index.php/Asus_RT-N66U#WPS_button_to_Clear_NVRAM Clear settings (Clear NVRAM)] | ||
- | + | =Revert to original ASUS firmware= | |
+ | # Download firmware from ASUS web site | ||
+ | # Reset to Factory Default Settings or clear NVRAM | ||
+ | # Use the DD-WRT web gui: 'Administration -> Firmware upgrade', to upload the ASUS firmware file you downloaded in step 1. | ||
+ | # Reset to Factory Default Settings or clear NVRAM | ||
- | + | =Mods= | |
- | == | + | ==Internal MicroSD card== |
- | + | The N66U has an unused internal MicroSD card slot, but note that USB (and thus MMC) is not supported on K2.6 builds. However, it is working on K3.x builds. See [http://svn.dd-wrt.com/ticket/2580 SVN ticket] | |
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | + | ||
- | = | + | #Open the case |
+ | #* Unscrew the four screws at the bottom | ||
+ | #* Then you want to release the plastic clips that holds the top and bottom parts together. | ||
+ | #* Pry the bottom case outward, which has the male clips. | ||
+ | #* For future access, it is recommended to either snip off the female "U" clips on the top cover, or round off the square edges on the male part of the clip with a nail file. | ||
+ | #Install MicroSD card | ||
+ | #Enable USB features to utilize the MicroSD card | ||
+ | *In addition to DD-WRT NAS features, the extra storage can be used to install Optware or [[Adding_Software_Packages_using_Entware-3X|Entware-3X (recommended over Optware)]] with K3.x builds: [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=156013 OTRW Take 2] | ||
+ | For easier access, see below. | ||
- | + | ==Case Top Mod== | |
+ | Spacers (~1/4" to 10mm) can be installed to elevate the case top, which allows easier access to the MicroSD card, and also improve cooling. A piece of dark foam and hole punch can be used to retain the top cover LED lighting. | ||
- | + | ==Overclocking== | |
+ | Overclocking works since CFE 1.0.1.3, while underclocking worked prior to that. Overclocking may cause instability, or services (like QoS) to behave unpredictably | ||
+ | *Recommended to improve cooling or ventilation when overclocking, like the case top mod | ||
+ | *jwh7 has run @663MHz (CFE 1.0.1.9) without issue for 3 years, with an elevated case top | ||
+ | *There is one report of QoS degradation at 632Mhz with K3.X big r27360 (06/18/15) | ||
- | === | + | =Power Consumption= |
- | * | + | Asus RT-N66U (measured with a kill-a-watt meter that has 0.000 resolution) |
+ | * PSU default numbers: 19V, 1.58A => max 30W, so there is also power for any USB devices. | ||
+ | * PSU standby usage: 0.06W (only the PSU is plugged in, no Router is connected) | ||
+ | * Unit running idle: 9.8W (Radio enabled, but no network cables in LAN or WAN ports) | ||
+ | * Network cables connected: 10.6W (Radio enabled, and wires connected to WAN port and 1 LAN port) | ||
+ | * 2.4GHz Radio usage: 0.9W (difference with 2.4GHz Radio On or Off) | ||
+ | * 5GHz Radio usage: 1.5W (difference with 5GHz Radio On or Off) | ||
- | + | =Notes= | |
- | + | ==Reset button for Recovery== | |
+ | Pressing the Reset button (labeled like ' > o < ') at powerup will put the N66U into recovery mode. | ||
+ | *Press and hold the reset button then plug in power until the power LED starts blinking. Access recovery mode at 192.168.1.1. | ||
- | + | ==WPS button to Clear NVRAM== | |
+ | Pressing the WPS button at powerup will reset (clear NVRAM) to default settings. | ||
+ | *Press and hold the WPS button while plugging in the power for about ten seconds. All the LEDs should flash, indicating settings have been reset to default settings. | ||
- | + | ==NVRAM issue== | |
+ | '''<font color="red">IMPORTANT: DO NOT USE K2.6 builds</font> if using CFE v1.0.1.3 (64K nvram) or NEWER!!!'''<br> | ||
+ | At launch, the RT-N66U was limited to 32k nvram. However, CFE (bootloader) version 1.0.1.3 added 64k nvram support around April 2013, but was not compatible with DD-WRT firmware at that time. For details, see these forum links to historical nvram and 64K implemention discussions: [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=86437&postdays=0&postorder=asc&highlight=otrw+light&start=1022 Fractal comments] and [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=163479&start=217 "RT-N66 CFE Thread"] | ||
- | + | This was resolved with DD-WRT K3X builds (kernel 3.x) which extended nvram to 64k, and can be used for any CFE version. It was eventually [https://forum.dd-wrt.com/phpBB2/viewtopic.php?p=1112621#1112621 extended to 256k]. | |
- | + | More historical info: http://charleswilkinson.co.uk/2012/12/22/dd-wrt-on-the-asus-rt-n66u-with-64k-cfe/ | |
- | + | ||
- | + | '''For newer CFE version updates''' and procedures see here: [https://www.snbforums.com/threads/cfe-bootloader-update.8259/ SNB Forums]<br> | |
- | + | Note: CFE is a bootloader for routers. The CFE is what loads the firmware when using ASUS Recovery Utility (and/or a TFTP tool) | |
- | + | NOTE: Why does the wiki not state to use the K26 nv64k upgrade images with the updated CFE? -kp69 | |
- | == | + | ==CFE Version (or Update)== |
- | + | [[Asus_RT-N66U#DD-WRT_Alternatives|AsusWRT-Merlin]] can be installed to enable telnet/ssh. telnet/ssh can then be used to check the CFE version as well as update the CFE version. DD-WRT can then be flashed directly from Asuswrt-Merlin | |
- | * | + | Find the CFE version: |
+ | *in telnet/ssh type: nvram get bl_version or strings /dev/mtd0ro | grep bl_ver | ||
- | * In the Asus Recover utility Access the router’s built in recovery mode by issuing 192.168.1.1 in browser field. | ||
- | + | To update the CFE version: | |
+ | * https://deviwiki.com/wiki/ASUS_RT-N66U/CFE_bootloader_update | ||
- | * | + | ==K3.X Builds== |
+ | *Use RT-N66U.trx ''big'' or ''mega'' builds in the ''Broadcom_K3X'' folder. [https://forum.dd-wrt.com/phpBB2/viewtopic.php?p=1150414 Forum note] about the difference between ''mega'' and ''big'' | ||
+ | *See [[Firmware_FAQ#Where_do_I_download_firmware.3F|Where do I download firmware]] for links and read forum build threads. | ||
- | + | Note: do NOT use build 40559 - 40559 is broken for most routers, despite being the recommended build for many routers in the Router Database. Search forum "New build" to get the latest updated info about builds (noted Aug 2020). | |
- | + | ==K2.6 Builds== | |
- | + | USB (and thus MMC) also does not work in K2.6 builds. USB devices cause a kernel panic: see [http://svn.dd-wrt.com/ticket/2580 SVN ticket]. Use a K3.x build (see above), which also works around the NVRAM issue. | |
- | : | + | |
- | + | ||
- | + | ||
- | + | '''NOTE:''' All K2.6 builds between 43136 and 44112 are broken. [https://forum.dd-wrt.com/phpBB2/viewtopic.php?p=1213600#1212757 REF] | |
- | + | == DD-WRT Alternatives == | |
+ | User Merlin implemented a solution in mid-2012 to extend the original 32k NVRAM CFE to ~60k NVRAM in firmware | ||
+ | * After 380.70 Asuswrt-Merlin stopped supporting RT-N66U. So earlier versions will still work (to enable SSH/Telnet) | ||
+ | ** Homepage: https://asuswrt.lostrealm.ca/ | ||
+ | ** Download: https://sourceforge.net/projects/asuswrt-merlin/files/ | ||
+ | **Source code: https://github.com/RMerl/asuswrt-merlin/ | ||
+ | * For a Asuswrt-Merlin version that still supports RT-N66U | ||
+ | ** see: [https://www.snbforums.com/threads/fork-asuswrt-merlin-374-43-lts-releases-v44ea.18914/ snbforums post] where the first entry keeps getting updated with the latest information. | ||
- | + | TomatoUSB [http://tomato.groov.pl/ Shibby] also implemented a 64k NVRAM solution for 32K NVRAM CFE in 2012. | |
- | + | [https://www.freshtomato.org/ FreshTomato] also supports this device and includes the 64K nvram solution from Shibby. | |
- | = | + | ==Historical Build Information== |
- | + | This is only potentially relevant if using builds from 2015 and earlier. | |
- | + | *If already running a custom 64K Build like Fractal or Kong with CFE 1.0.1.3, [ftp://ftp.dd-wrt.com/betas/2015/02-04-2015-r26138/broadcom_K3X/dd-wrt.v24-26138_NEWD-2_K3.x_mega-nv64k.bin 26138 mega nv64k] must be used to upgrade. Since K2.6 Builds have an embedded check, you need to use those special nvXXk trailed images. On K3.X this check has been removed and you can simply upgrade from a previous K3.X. | |
- | + | *With K3.X Broadcom builds, the CFE version is less concerning since DD-WRT detects it automatically to extend the 32KB limitation. | |
- | + | *Build 24461 BRICKS the RT-N66U, but recover is possible through the mini CFE web interface. | |
- | = | + | |
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- | * | + | |
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- | + | ||
+ | ==Performance== | ||
<pre> | <pre> | ||
- | Test Description | + | Test Description RT-N66U |
- | WAN - LAN | + | WAN - LAN 732 Mbps |
LAN - WAN 729 Mbps | LAN - WAN 729 Mbps | ||
- | Total Simultaneous | + | Total Simultaneous 810 Mbps |
Maximum Simultaneous Connections 34,925 | Maximum Simultaneous Connections 34,925 | ||
Firmware Version 3.1.0.3.90 (stock firmware number) | Firmware Version 3.1.0.3.90 (stock firmware number) | ||
- | </pre> | + | </pre> |
+ | [http://www.smallnetbuilder.com/wireless/wireless-reviews/31687-asus-rt-n66u-dark-knight-dual-band-wireless-n900-gigabit-router-reviewed?start=2 Sources] and [http://www.smallnetbuilder.com/lanwan/lanwan-howto/31103-how-we-test-hardware-routers-revision-3 testing methods] | ||
- | = | + | ==LAN/WAN issue== |
- | * [http://www.dd-wrt.com/phpBB2/viewtopic.php?t= | + | There should be no ''vlan0ports'' in nvram for the N66U switch: [https://www.dd-wrt.com/phpBB2/viewtopic.php?p=986347#986347] and [https://www.dd-wrt.com/phpBB2/viewtopic.php?p=936405#936405]<br> |
+ | |||
+ | ==Links== | ||
+ | Primary forum threads | ||
+ | * [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=171783 One User's Guide] - A users guide for flashing RT-N66U | ||
+ | * Possible ways to update CFE (once a 32k+ CFE is released for this router), see [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=86437&postdays=0&postorder=asc&start=496 LOM post] | ||
+ | *[[Linking_Routers| Linking Routers]] to cover a bigger area with WiFi | ||
+ | *Wireless tweaking: [[Basic_Wireless_Settings|Basic Wireless Settings]] and [[Advanced_wireless_settings|Advanced Wireless Settings]] | ||
+ | *External antennas: [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=43810 The CATFISH thread] | ||
+ | * A good 2020 [https://forum.dd-wrt.com/phpBB2/viewtopic.php?t=325439 forum thread] | ||
+ | |||
+ | Additional forum threads | ||
* [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=153609 Forum: Flashing discussion] | * [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=153609 Forum: Flashing discussion] | ||
* [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=153609&postdays=0&postorder=asc&start=5 Forum: Reason for starting from Build 18946] | * [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=153609&postdays=0&postorder=asc&start=5 Forum: Reason for starting from Build 18946] | ||
* [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=154818 Forum: N66U and 32k/64k NVRAM issue] | * [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=154818 Forum: N66U and 32k/64k NVRAM issue] | ||
- | * [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=155642 Forum: | + | * [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=155642 Forum: Open case to add MicroSD card], and a 32Gb card tested [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=155642&start=8 here] |
* [http://www.techinfodepot.info/index.php/Asus_RT-N66U_B1 techinfodepot.info on RT-N66U] | * [http://www.techinfodepot.info/index.php/Asus_RT-N66U_B1 techinfodepot.info on RT-N66U] | ||
* [http://www.smallnetbuilder.com/wireless/wireless-reviews/31687-asus-rt-n66u-dark-knight-dual-band-wireless-n900-gigabit-router-reviewed SmallNetBuilder Review] | * [http://www.smallnetbuilder.com/wireless/wireless-reviews/31687-asus-rt-n66u-dark-knight-dual-band-wireless-n900-gigabit-router-reviewed SmallNetBuilder Review] | ||
* [http://service.asus.com/demoui/RT-N66U/EN/index.html Asus Stock UI demo] | * [http://service.asus.com/demoui/RT-N66U/EN/index.html Asus Stock UI demo] | ||
- | |||
- | * WAN issue fixed in svn18835, see [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=86437&postdays=0&postorder=asc&start=214 Forum post, Eko] | ||
- | * Serial inside is: 8, n, 1, no flow control, 115200. | ||
- | * Possible ways to update CFE (once a 32k+ CFE is released for this router), see [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=86437&postdays=0&postorder=asc&start=496 Forum, LOM] | ||
- | * Positive report of running svn18740, see [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=86437&postdays=0&postorder=asc&start=706 Forum post] | ||
- | |||
- | ==Generally good to know == | ||
- | * [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=51486 Peacock Thread-FAQ: EVERYTHING you NEED to know! Really!!] All the basics about DD-WRT on Broadcom based routers - A MUST READ Thread!!! | ||
- | * Get the most speed out of your [[Wireless-N_Configuration|wireless-N technology]] | ||
- | * [http://www.dd-wrt.com/phpBB2/viewtopic.php?t=43810 The CATFISH thread - external antenna choice and use] If you need a better WiFi connection - get a better antenna!!! or | ||
- | * [[Linking_Routers]] to cover a bigger area with WiFi | ||
[[Category:Asus guides]] | [[Category:Asus guides]] |
Current revision
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Contents |
[edit] Hardware Specifications
CPU | Broadcom 4706 @ 600MHz |
---|---|
Flash/RAM | 32MB / 256MB |
Wireless support | 2.4GHz and 5GHz bands |
Wireless controller | Broadcom BCM4331 |
MIMO config | 3x3 (both bands) (see Ref: forum) |
ETH chip | Broadcom BCM4706 |
Switch | Broadcom BCM53125 |
Ports | Gigabit LAN (4) and WAN (1) |
USB | 2x USB 2.0 |
Other | Micro SDHC socket (internal) |
Power supply | DC Output, 19 V, max. 1.58 A current (=> max 30W) |
Serial header | 8, n, 1, no flow control, 115200. |
[edit] Installation Instructions
Read the Firmware FAQ, Peacock Announcement, new build, and model-specific threads.
WARNING: This 'Dark Night' presents significant risk to bricking that requires careful adherence to the installation process, however, there is a built-in and robust Recovery Mode.
NOTE: The NVRAM issue has been resolved in newer CFE versions (and K3X builds).
NOTE: It is highly recommended to use Private, Incognito, InPrivate browsing mode with no extensions or add-ons enabled, and no passwords saved to the browser in any way when flashing or accessing the webUI. It is preferred to use a Portable browser such as Firefox, Firefox ESR, or Pale Moon. If you run into issues, clear browser cache or override with CTRL+F5
[edit] Preparation
- If upgrading to DD-WRT from other firmwares, then use a *.trx file, as in *_RT-N66U.trx file for initial flash and upgrades, or only half the memory will be available (with ASUS routers, using a *.trx file is always a safe bet).
- If you are upgrading from one version of DD-WRT to a different (newer/older) version of DD-WRT, you can also use the firmwares that end in *.bin. as in _mega.bin or _big.bin
- IMPORTANT: Determine what version of CFE you have on your router, if CFE v1.0.1.3 (64K nvram) or 'NEWER' - DO NOT USE K2.6 builds
- If using Older CFE (32K nvram) you can use K2.6 builds
- Reset BEFORE and AFTER firmware upload. If upgrading from DD-WRT to a newer version of DD-WRT, then before is (mainly) optional.
- Refer to the Notes section below if any of the following steps are confusing
[edit] Upload via Web GUI
- Reset NVRAM via WPS button , or select WebGUI option: Factory Default settings.
- Upload the DD-WRT build using the stock web GUI (use file ending in .trx or .bin, according to description under Preparation).
- Wait until the router reboots itself, which can take at least 10 minutes (some times 30 minutes or more). Be patient and wait until you get a response from both ping and the routers WebGUI when you use your PC to access the router.
- Reset NVRAM via WPS button, or select WebGUI option: Factory Default settings. Wait for the router to reboot!!
Note: If you are having trouble uploading a newer version of DD-WRT, using the WebGUI, then you might want to try to use a different browser. Sometimes it solves the problem.
[edit] Upload via ASUS Recovery Utility
- Set your computer to a static IP (e.g. 192.168.1.12), subnet 255.255.255.0, default gateway 192.168.1.1
- Put router into recovery mode by holding down the reset button while powering up the router, wait until the power led is blinking slowly, then release the reset button.
- Access the Asus CFE recovery mode by issuing 192.168.1.1 in browser field.
- Browse to select the DD-WRT trailed build (N66U big or mega .trx) then click Upload.
- Wait until the router reboots itself, which can take at least 10 minutes.
- If it doesn't reboot after 30 minutes, power off for 10 seconds, then reset via WPS
- Reset (via WPS) or reenter recovery mode and select to Restore defaults NVRAM values
- (Optional?) When it completes (should be quick), type this in the browser field then press enter:
- http://192.168.1.1/do.htm?cmd=nvram+commit
- Wait until the router reboots itself, then access the DD-WRT GUI at 192.168.1.1 to set a password.
[edit] Switching from Tomato
- Navigate to the Tomato firmware update page
- Administration -> Upgrade
- Upload the firmware you downloaded in step 1
- The router will reset several times and change its IP address to the default one (192.168.1.1).
- Navigate to http://192.168.1.1/Factory_Defaults.asp
- The login credentials have been reset to the default dd-wrt username/password (root/admin)
- Set "Restore Factory Defaults" to yes and click "Apply Settings"
- After reboot, set a new user/password
- Note: Reset to factory defaults after flashing from Tomato to DD-WRT to avoid undesired behavior and instability.
[edit] Upgrade to newer DD-WRT
- Clear settings (Clear NVRAM)
- Router should revert to default IP (192.168.1.1), so you may have to change your client's IP to the same subnet (e.g. 192.168.1.2).
- Use browser to navigate to 192.168.1.1
- DD-WRT GUI: Administration -> Firmware upgrade
- Clear settings (Clear NVRAM)
[edit] Revert to original ASUS firmware
- Download firmware from ASUS web site
- Reset to Factory Default Settings or clear NVRAM
- Use the DD-WRT web gui: 'Administration -> Firmware upgrade', to upload the ASUS firmware file you downloaded in step 1.
- Reset to Factory Default Settings or clear NVRAM
[edit] Mods
[edit] Internal MicroSD card
The N66U has an unused internal MicroSD card slot, but note that USB (and thus MMC) is not supported on K2.6 builds. However, it is working on K3.x builds. See SVN ticket
- Open the case
- Unscrew the four screws at the bottom
- Then you want to release the plastic clips that holds the top and bottom parts together.
- Pry the bottom case outward, which has the male clips.
- For future access, it is recommended to either snip off the female "U" clips on the top cover, or round off the square edges on the male part of the clip with a nail file.
- Install MicroSD card
- Enable USB features to utilize the MicroSD card
- In addition to DD-WRT NAS features, the extra storage can be used to install Optware or Entware-3X (recommended over Optware) with K3.x builds: OTRW Take 2
For easier access, see below.
[edit] Case Top Mod
Spacers (~1/4" to 10mm) can be installed to elevate the case top, which allows easier access to the MicroSD card, and also improve cooling. A piece of dark foam and hole punch can be used to retain the top cover LED lighting.
[edit] Overclocking
Overclocking works since CFE 1.0.1.3, while underclocking worked prior to that. Overclocking may cause instability, or services (like QoS) to behave unpredictably
- Recommended to improve cooling or ventilation when overclocking, like the case top mod
- jwh7 has run @663MHz (CFE 1.0.1.9) without issue for 3 years, with an elevated case top
- There is one report of QoS degradation at 632Mhz with K3.X big r27360 (06/18/15)
[edit] Power Consumption
Asus RT-N66U (measured with a kill-a-watt meter that has 0.000 resolution)
- PSU default numbers: 19V, 1.58A => max 30W, so there is also power for any USB devices.
- PSU standby usage: 0.06W (only the PSU is plugged in, no Router is connected)
- Unit running idle: 9.8W (Radio enabled, but no network cables in LAN or WAN ports)
- Network cables connected: 10.6W (Radio enabled, and wires connected to WAN port and 1 LAN port)
- 2.4GHz Radio usage: 0.9W (difference with 2.4GHz Radio On or Off)
- 5GHz Radio usage: 1.5W (difference with 5GHz Radio On or Off)
[edit] Notes
[edit] Reset button for Recovery
Pressing the Reset button (labeled like ' > o < ') at powerup will put the N66U into recovery mode.
- Press and hold the reset button then plug in power until the power LED starts blinking. Access recovery mode at 192.168.1.1.
[edit] WPS button to Clear NVRAM
Pressing the WPS button at powerup will reset (clear NVRAM) to default settings.
- Press and hold the WPS button while plugging in the power for about ten seconds. All the LEDs should flash, indicating settings have been reset to default settings.
[edit] NVRAM issue
IMPORTANT: DO NOT USE K2.6 builds if using CFE v1.0.1.3 (64K nvram) or NEWER!!!
At launch, the RT-N66U was limited to 32k nvram. However, CFE (bootloader) version 1.0.1.3 added 64k nvram support around April 2013, but was not compatible with DD-WRT firmware at that time. For details, see these forum links to historical nvram and 64K implemention discussions: Fractal comments and "RT-N66 CFE Thread"
This was resolved with DD-WRT K3X builds (kernel 3.x) which extended nvram to 64k, and can be used for any CFE version. It was eventually extended to 256k.
More historical info: http://charleswilkinson.co.uk/2012/12/22/dd-wrt-on-the-asus-rt-n66u-with-64k-cfe/
For newer CFE version updates and procedures see here: SNB Forums
Note: CFE is a bootloader for routers. The CFE is what loads the firmware when using ASUS Recovery Utility (and/or a TFTP tool)
NOTE: Why does the wiki not state to use the K26 nv64k upgrade images with the updated CFE? -kp69
[edit] CFE Version (or Update)
AsusWRT-Merlin can be installed to enable telnet/ssh. telnet/ssh can then be used to check the CFE version as well as update the CFE version. DD-WRT can then be flashed directly from Asuswrt-Merlin
Find the CFE version:
- in telnet/ssh type: nvram get bl_version or strings /dev/mtd0ro | grep bl_ver
To update the CFE version:
[edit] K3.X Builds
- Use RT-N66U.trx big or mega builds in the Broadcom_K3X folder. Forum note about the difference between mega and big
- See Where do I download firmware for links and read forum build threads.
Note: do NOT use build 40559 - 40559 is broken for most routers, despite being the recommended build for many routers in the Router Database. Search forum "New build" to get the latest updated info about builds (noted Aug 2020).
[edit] K2.6 Builds
USB (and thus MMC) also does not work in K2.6 builds. USB devices cause a kernel panic: see SVN ticket. Use a K3.x build (see above), which also works around the NVRAM issue.
NOTE: All K2.6 builds between 43136 and 44112 are broken. REF
[edit] DD-WRT Alternatives
User Merlin implemented a solution in mid-2012 to extend the original 32k NVRAM CFE to ~60k NVRAM in firmware
- After 380.70 Asuswrt-Merlin stopped supporting RT-N66U. So earlier versions will still work (to enable SSH/Telnet)
- Homepage: https://asuswrt.lostrealm.ca/
- Download: https://sourceforge.net/projects/asuswrt-merlin/files/
- Source code: https://github.com/RMerl/asuswrt-merlin/
- For a Asuswrt-Merlin version that still supports RT-N66U
- see: snbforums post where the first entry keeps getting updated with the latest information.
TomatoUSB Shibby also implemented a 64k NVRAM solution for 32K NVRAM CFE in 2012.
FreshTomato also supports this device and includes the 64K nvram solution from Shibby.
[edit] Historical Build Information
This is only potentially relevant if using builds from 2015 and earlier.
- If already running a custom 64K Build like Fractal or Kong with CFE 1.0.1.3, 26138 mega nv64k must be used to upgrade. Since K2.6 Builds have an embedded check, you need to use those special nvXXk trailed images. On K3.X this check has been removed and you can simply upgrade from a previous K3.X.
- With K3.X Broadcom builds, the CFE version is less concerning since DD-WRT detects it automatically to extend the 32KB limitation.
- Build 24461 BRICKS the RT-N66U, but recover is possible through the mini CFE web interface.
[edit] Performance
Test Description RT-N66U WAN - LAN 732 Mbps LAN - WAN 729 Mbps Total Simultaneous 810 Mbps Maximum Simultaneous Connections 34,925 Firmware Version 3.1.0.3.90 (stock firmware number)
[edit] LAN/WAN issue
There should be no vlan0ports in nvram for the N66U switch: [1] and [2]
[edit] Links
Primary forum threads
- One User's Guide - A users guide for flashing RT-N66U
- Possible ways to update CFE (once a 32k+ CFE is released for this router), see LOM post
- Linking Routers to cover a bigger area with WiFi
- Wireless tweaking: Basic Wireless Settings and Advanced Wireless Settings
- External antennas: The CATFISH thread
- A good 2020 forum thread
Additional forum threads