[N66U] DFS channels missing in Merlin-Fork

[shobhitk]

Hi everyone,
I have flashed Merlin fork version - 33E7 on my N66U. Working nicely and pretty stable as well.

I was also hoping that i would get access to DFS channels on N66U as people here have mentioned about using them on their N66U with merlin. However DFS channels are still not visible in the channel selection drop down list under 5ghz band.

Is there a setting or something for it to work?

Kindly throw some light. Thanks

 

[john9527]

Is there a setting or something for it to work?

Have a look at the 'Merlin_Fork_Options.txt' file packaged with the firmware. The instructions for activating DFS support (as well as some other fork options) can be found there.

 

[shobhitk]

Have a look at the 'Merlin_Fork_Options.txt' file packaged with the firmware. The instructions for activating DFS support (as well as some other fork options) can be found there.

Thanks for the prompt response john. I'll check it out.

And thanks for providing the useful fork of merlin-wrt to the community!

 

[shobhitk]

ok so the txt file mentions that the customization of DFS channels is available to only EU models of N66U. I guess i am not on a EU model.

A few queries:-

1) If i dont have the EU model, can i still get DFS?
2) If at all DFS starts working, can i revert back safely and disable DFS?

 

[Grisu]

ad 2) if you select dedicated (allowed) channels instead of auto than you wont get any problem.

 

[john9527]

A few queries:-

1) If i dont have the EU model, can i still get DFS?

It's actually whatever your region would normally support in terms of channel selection, it doesn't override regulatory requirements. EU DFS enablement being the most common. It won't for example allow you to use DFS channels in the US.

2) If at all DFS starts working, can i revert back safely and disable DFS?

Just undo the nvram change, or as @Grisu said, select a non-DFS channel.

 

[shobhitk]

I ran the commands 'as given' in the txt file you mentioned. The router restarted but the channels available under the 5ghz mode remained unchanged. The 'Auto select channels including DFS' box also did not appear.

 

[Grisu]

on 68U easily you could change region in cfe and set it to EU-country, dont know how done on 66U, google for it.

maybe a help: https://www.snbforums.com/threads/cant-change-country-on-rt-n66u.15047/

 

[ColinTaylor]

I ran the commands 'as given' in the txt file you mentioned. The router restarted but the channels available under the 5ghz mode remained unchanged. The 'Auto select channels including DFS' box also did not appear.

What region was your router manufactured for? Go to the Wireless - Professional page, select the 5GHz band and look at the orange text at the bottom of the page. It should say something like (EU/13) or (US/01), etc.

 

[shobhitk]

What region was your router manufactured for? Go to the Wireless - Professional page, select the 5GHz band and look at the orange text at the bottom of the page. It should say something like (EU/13) or (US/01), etc.

For the 5ghz mode it is being reported as - (Q2/0)

 

[ColinTaylor]

For the 5ghz mode it is being reported as - (Q2/0)

OK thanks. That's quite awkward. Q2 was a special "engineering mode" that was used on the US routers. I think it gave extra power but it doesn't include the DFS channels. Are you actually in the US?

 

[john9527]

For the 5ghz mode it is being reported as - (Q2/0)

Q2 is actually an alternate region code for the US....I know it's the stock setting for some of the newer AC68U variants (my AC68P uses it). Sounds like they also started using it on the N66 as well. Since it's a US code, DFS channels aren't supported.

 

[shobhitk]

Q2 is actually an alternate region code for the US....I know it's the stock setting for some of the newer AC68U variants (my AC68P uses it). Sounds like they also started using it on the N66 as well. Since it's a US code, DFS channels aren't supported.

i see. but john i have seen people here changing their region codes through command line. is there any chance for it to work if i change it to some other region, maybe EU?

 

[ColinTaylor]

Since it's a US code, DFS channels aren't supported.

Is the lack of DFS something specific to the US N66U's? Perhaps they weren't originally certified for it, like was the case with the EU models. It looks to me like the US AC68's use code Q2/12 which does have DFS channels (maybe because they're AC not N?). I'm just wondering whether DFS could be legally added now that the wireless driver has been updated, similar to what happened for the EU models. Just a thought.

 

[john9527]

We need someone running an N66 to check the settings when running the last Merlin 380 release or a recent Asus stock release. (I can't see what they are doing anymore as this set of functions is now closed source).

nvram get regulation_domain_5G
nvram get pci/2/1/regrev

 

[RMerlin]

Why do you want so badly to use DFS channels anyway? These channels should only be used as a last resort, as

a) they conflict with radar devices, meaning that at any time you might be forced to leave the channel if radar activity is detected
b) a lot of client devices have trouble working with DFS channels
c) DFS is not supported in your region, meaning changing region to access unavailable channels is illegal

 

[john9527]

c) DFS is not supported in your region, meaning changing region to access unavailable channels is illegal

Actually, it's just almost impossible to keep up with the FCC. The latest 'New Rules', allow for DFS channel support in the US (I had to look it up...ALL the DFS channel are now allowed)

 

[shobhitk]

@RMerlin - so that more channels are available for use when needed.

@john9527 - thats good news!

 

[ColinTaylor]

@john9527 - thats good news!

Only if you're willing to provide John with the information he asked for in post #15. Even then he might not be able to implement it.

 

[john9527]

Only if you're willing to provide John with the information he asked for in post #15. Even then he might not be able to implement it.

And, I would be willing to bet most (all?) existing client drivers aren't going to be updated to support the new rules.