Hard reset or 30/30/30

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DO NOT attempt to reset or power cycle the router while it is still in the process of upgrading!
Wait a couple of minutes after upgrade is complete and the router has rebooted itself.


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DO NOT attempt to hard reset/30-30-30 or erase the nvram on a Linksys EA series router as it may erase the CFE and brick your routerref


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DO NOT do a 30-30-30 hard reset on any ARM router. See below for what to do: Hard Reset on ARM and other newer routers.


Contents


[edit] 30/30/30 reset

NOTE: This should only be done on older Broadcom MIPSR1 routers (i.e. WRT54* and it's clones).
NOTE: On newer routers, ex: Asus N66U, this will put them in recovery mode instead.

The following procedure will clear out the NVRAM and set dd-wrt back to default values:

  • With the unit powered on, press and hold the reset button on back of unit for 30 seconds
  • Without releasing the reset button, unplug the unit and hold reset for another 30 seconds
  • Plug the unit back in STILL holding the reset button a final 30 seconds
    (please note that this step can put Asus devices into recovery mode...see note below!)

This procedure should be done BEFORE and AFTER every firmware upgrade/downgrade.

Do not use configuration restore if you change firmware builds (different svn build numbers).

[NOTE] - For Asus units, the standard 30/30/30 method will reset the router but you will need to use the Restore button followed by a Power cycle. The only exception (so far) is the RT-N16 model, follow the same method as stated above but use the WPS button instead of the Restore button. If all else fails to reset you can also do it by command line (all units). Login to the router via telnet/ssh and issue the command "erase nvram". This will reset the nvram partition to defaults for this Make of router.....redhawk

[edit] Hard Reset on ARM and other newer routers

Do not use 30-30-30 hard reset on any ARM router. Reference: Kong

  1. Power off the unit.
  2. Press and hold on to the WPS button.
  3. While holding down the WPS button, power on the unit.
  4. Keep holding the WPS button until the power led starts to blink a few times.
  5. When the power led starts blinking / flashing, release the WPS button.

[edit] Erasing NVRAM

An alternative method to restore DD-WRT to default settings without using the reset button is via telnet or SSH. This is useful if locked out of the web interface or the reset button is disabled, broken, or 30/30/30 doesn't work. This should not be done on some models, so refer to the device wiki and/or forum device threads.

Using DD-WRT with Telnet (or SSH) for builds after 18 Apr 2018 (35770 and later):

nvram erase && reboot

Calling erase nvram will still erase the nvram mtd, but on reboot (or any other action) the nvram is saved to mtd from RAM, so this will not wipe everything unless power is removed right after the erase nvram. However, nvram erase clears the nvram in RAM then then writes to flash, but does not zero out the flash from first to last block. (Reference: Kong's comments)


Builds from 18 Apr 2018 or older (35681 and prior) use:

erase nvram && reboot

Alternate direct method, but not recommended and should be used with caution!

mtd -r erase nvram

Note: The command in Broadcom CFE (bootloader) mode is `nvram erase`

[CAUTION] - This should not be used on some devices. For example, on the Asus WL-500g and Motorola WR850G, the bootloader will not create default values and the device will not boot properly. On a Siemens SE505 V1, the router will no longer be accessible and must be reflashed with stock firmware on IP address 192.168.1.1 (NOT 192.168.2.1 as the installation procedure says)

[edit] Default password

If the reset is successful, after reboot the GUI will prompt to set a User and Password (except for very old builds).