Installing dd-wrt on Linksys EA6900

Follow the guide at http://www.dd-wrt.com/phpBB2/viewtopic.php?t=291230

32k nvram bug

The default bootloader on the Linksys EA6900 has a bug when more than 32k of nvram is in use. Either update the bootloader, or don't use over 32k. To prevent using too much nvram: turn off unnecessary services, don't use ssh key-based authentication.

Add following script to the startup section to remove unset variables:

for line in `nvram show | grep =$ `; do var=${line%*=}; nvram unset $var; done

Flashing

First flash a small image: ftp://ftp.dd-wrt.com/betas/2013/12-22-2013-r23194/linksys-ea6900/ Afterwards an up-to-date image can be loaded. Just browse ftp://ftp.dd-wrt.com/betas . It might be prudent to take an image that's a week old. When bugs are found, a new revision is often uploaded on the next day, otherwise releases are weekly.

In this case I used: ftp://ftp.dd-wrt.com/betas/2016/06-06-2016-r29837/linksys-ea6900/