[xiii1408]

Just writing a note here in case anyone else encounters this issue.

I recently upgraded my ASUS RT-N66U router's firmware from 08/01/24 to 05/16/25. I did the 1) Factory Reset, 2) Flash Upgrade, 3) Factory Reset procedure described in the Wiki.

I encountered two issues:

1) After the second factory reset, the CTF option was not available. Under Setup -> Basic Setup I simply saw "Shortcut Forwarding Engine" with a radial button for Enabled/Disabled. I also noticed several other settings that looked funny ("null" where the new option "Cell Density" should have been under Wireless -> Basic Settings). A reboot fixed this problem, and the "CTF" option appeared as expected.

2) After enabling CTF, CTF appeared to be disabled. My wired Internet speeds were pinned at ~100 Mbps, whereas before the firmware upgrade I was seeing 600-800 Mbps. Setting the "Shortcut Forwarding Engine" option to "SFE" seemed to work, as I got around ~300 Mbps as expected. After a number of factory resets and reboots, this eventually cleared up, and CTF now functions as expected (600-800 Mbps Internet speeds).

So, if you have recently upgraded and CTF is not available or acting funky, try factory resetting *then rebooting* before enabling the option. The new firmware is definitely not broken, so keep trying.

(I also noticed much lower WiFi speeds unless I set my 5 GHz connection as having Network Mode "Mixed," but that's probably completely unrelated.)

[kernel-panic69]

You have to reboot to load the SFE or CTF kernel modules for them to work after enabling them and clicking Save. This is by design. Save and Apply doesn't do anything good in this respect.