5GHz not working

[Treadler]

I've done that twice now - with the same results. First time was just prior to installing Merlin & 2nd time was just prior to reistalling stock.

As stated, should be AFTER.

 

[Preskitt.man]

OK - basically no progress. Here's sequence of events since last post.
1) With Stock installed - did a system reset with initialize
Could not connect to 5GHz except with no security enabled
2) Uploaded and installed Merlin (384-11.2)
3) After a reboot into Melin, did a System reset with initialize
Could not connect to 5GHz . Fails every time with "Failed to obtain an IP Address"
Turned off MIMO and Beamforming: No change
Changed modulation scheme to MCS 9: No change
Changed channel from Auto to Channel 36 and bandwidth to 20: No change
What does work (but not a satisfactory solution) is to leave all those values at their original settings BUT turn WI-FI security. Make it an open connection

 

[Grisu]

OK - basically no progress. Here's sequence of events since last post.
1) With Stock installed - did a system reset with initialize

It's not done with initialize as we tried to explain you all the time.
Go exactly through the complete M&M process!
And turn off modem with line disconnected for 1/2hour too, to reset line and ISP.

 

[Preskitt.man]

Here's what was the process in it's entirety it was suggested I do:
"You need to do a full reset to factory defaults (including checking the 'Initialize all settings...' checkbox) after you first flash the firmware you want to use". This was later followed up by you with "you have to do it AFTER you installed new firmware and follow exactly each bit in the text!"

Ok - great . So to quote myself as you just did as well " With stock installed - did a system reset with initialize" . So, in other words, after the installation of the firmware - did a system reset with initialize". And as I subsequently said, after that did not resolve the problem, I installed Merlin and then (AFTER) did a system reset with initialize. And it still isn't working.

I am quite willing to spend the time to do things to reasonably try to fix this issue. And I greatly appreciate the help and advice I have received from you and others on this forum. Why do I think that this is a defective unit - because broadcasting a signal and accepting a connection attempt that provides the correct password is one of the fundamental aspects of a router. It should work out of the box with stock software as well as the great software from Merlin. It has not worked from the initial turn on of the router till right now. It does recognize a bad password and informs me of such. It does connect with an Open connection. It does everything quite properly with the 2.4 GHz channel. And my AC68U, connected to the same signal as passed through from this router connects with the 2.4 and 5 GHz channels, as it also did moments before I first installed the AC86U.

 

[dave14305]

And my AC68U, connected to the same signal as passed through from this router connects with the 2.4 and 5 GHz channels, as it also did moments before I first installed the AC86U.

I had asked earlier if you have tested with the AC68U turned-off. Sometimes odd things like this are caused by legacy gremlins in the house/network.

 

[Preskitt.man]

If I turn off the 86U, I would have no signal to the 68U. Basically signal comes in from outside Fiber connection (no modem) into the 86U; in addition to Wi-Fi, I have 3 ethernet connections coming out - one to my Dell Desktop - one to my wife's laptop in the far reaches of the kitchen - and one to the 68U in the Family Room which now servers as an Access Point. So, turn off the 86U, bye-bye to the 68U. However, when I first installed the 86U on Friday, immediately prior to that, the 68U was where the 86U is now and older Netgear router served as my Access Point. When the 68U was the direct recipient of the signal from the Fibre, it worked just fine on 2.4 GHz and 5 GHz. Frankly, not only would it be a physical pain to go back to that configuration just to further validate that the problem is in the 86U and not the connection from the Fiber, each time I go through this process, it is very disruptive to the household. We have cut the cord and depend on the internet for TV, Phone (wi-fi calling as cell signal is very weak), as well as general internet use on our various computers. And intellectually, I don't see at this point how it the problem is software/firmware in the box. Connecting a device to the incoming signal to provide Wi-Fi is a fundamental feature of a router.

 

[ColinTaylor]

If I turn off the 86U, I would have no signal to the 68U.

He said turn off the 68U, not the 86U. It's a long shot but worth eliminating it as some form of interference.

 

[dave14305]

He said turn off the 68U, not the 86U. It's a long shot but worth eliminating it as some form of interference.

It just struck me as suspicious that the old router wasn't mothballed, but is still on the network, albeit in a different role (AP vs Router). I don't know how much of its brains get erased switching from router mode to AP mode, since I've never needed an AP. Think of the prize if the longshot wins!

 

[Preskitt.man]

So - for completeness - I turned off the 68U (old router serving as an access point), reverted to WPA2-Personal for 5GH on the 86U and tried to connect. With the same results. "Failed to obtain an IP address". As before, it will detect a bad password, and it will connect with an Open connection.

 

[dave14305]

So - for completeness - I turned off the 68U (old router serving as an access point), reverted to WPA2-Personal for 5GH on the 86U and tried to connect. With the same results. "Failed to obtain an IP address". As before, it will detect a bad password, and it will connect with an Open connection.

I guess at this point you won't be confident in the router even if you find a way to get it to work. May as well plan to return/exchange it.

We can pull your strings all day if you let us, but in the end it's just a router and better to replace it and get on with life.

 

[L&LD]

So - for completeness - I turned off the 68U (old router serving as an access point), reverted to WPA2-Personal for 5GH on the 86U and tried to connect. With the same results. "Failed to obtain an IP address". As before, it will detect a bad password, and it will connect with an Open connection.

https://www.snbforums.com/threads/major-issues-w-rt-ac86u.56342/page-4#post-495710

The link above, if followed in the order provided, will either confirm that your router's 5GHz band is broken or not.

I am not sure what other customizations you've done to your setup, but I would recommend testing with all other network equipment turned off, unplugged and not connected via any Ethernet ports they may have. Simply disconnect all cabling (power, Ethernet, USB, etc.) between all your equipment for testing purposes.

The only devices you need to test with is the info in the link(s) above, the ISP's modem (or ONT connection) the router you'll be resetting and a laptop to connect wirelessly to it.

There should be nothing else powered up and certainly not connected (even if it is powered off) to the above.


So far, the process has worked for the original poster I was assisting.

https://www.snbforums.com/threads/major-issues-w-rt-ac86u.56342/page-4#post-495934

 

[Grisu]

and use only letters and digits for user and password (8-10 characters) and SSID.

 

[Preskitt.man]

When I did my testing, it was immediately following the reset (with initialization) and doing a basic setup. My SSID was unique from the SSID on the access point. My SSID was HomeNet-B. My password has periods in it (no other special characters). I have never seen advice to not do those things. And I know you have a very detailed full procedure to try and fix this, but frankly, I have a business to run here at home and my wife uses her phone, watches TV and uses her laptop, all of which depends in part on this router. I have never done anything that requires JFFS. I did try, just for S&G's renaming my SSID to HomeNetB (no dashes) and redid my password to remove the special characters. Still the same result. I have already contacted Amazon (where I got this router) and will be doing an exchange.

 

[Woody]

So here is a weird thing that might be relevant:

I run:

86U with Merlin 384.11
Mikrotik cAP ac

Both have different and unique SID's for the 2.4GHz and 5GHz - i.e. 4 discrete SID's - so I know exactly which AP and frequency I can see and connect to.

ALL my 5Ghz devices can see and connect to both the Mikrotik and 86U 5GHz AP's. That includes a mixture of Xiaomi, Samsung and Apple phones, and Microsoft Surface Pro 4's and Asus laptops etc EXCEPT an Amazon FIRE 7.

The FIRE can see and connect to, the 2.4GHz AP's AND can see and connect to the Mikrotik 5GHz AP BUT the fire cannot see the 86U 5GHz AP. It's not that it can't connect to it - it literally can't detect its existence.

I am in the UK and the FIRE was purchased from Amazon UK.

Now here is the interesting bit:

Both 5GHz AP's are running 80Mhz wide (so that's not the issue) but the Mikrotik 5GHz (that the FIRE can see and connect to) is channel 36 but the 86U is channel 100 (although not in the radar range).

I have no idea why the FIRE can't even see the 86U 5GHz on channel 100 - but it does indicate that all is not equal between devices.

 

[ColinTaylor]

I have no idea why the FIRE can't even see the 86U 5GHz on channel 100 - but it does indicate that all is not equal between devices.

That is not that unusual. I have a smart TV. It doesn't support the DFS channels (50 to 165) so it won't even attempt to detect them, let alone connect to them.

 

[Preskitt.man]

In the, there is no support for the DFS channels for general public use.

 

[ColinTaylor]

In the, there is no support for the DFS channels for general public use.

I think there's a word missing from that sentence.

 

[Preskitt.man]

Sorry - meant to say: In the US, there is no support for the DFS channels for general public use. Only channels in the US are 36-48 and 149-165.

 

[ColinTaylor]

Sorry - meant to say: In the US, there is no support for the DFS channels for general public use. Only channels in the US are 36-48 and 149-165.

Not true. DFS channels have been available in the US for over a decade (although whether or not a device is certified to use them is another matter).

https://www.cablefree.net/wirelesstechnology/wireless-lan/wlan-frequency-bands-channels/
https://en.data-alliance.net/legal-illegal-frequencies/?GTTabs=0
https://www.smallnetbuilder.com/bas...r-s-wi-fi-dynamic-frequency-selection-dfs-faq

 

[Preskitt.man]

Issue get even more wierd.
Went to system log and turned up log level to Debug.
Each time I tried to connect (for example my S8) , I would get the following 4 messages:
Jun 11 21:03:05 WLCEVENTD: eth6: Assoc B0:72:BF:FD:13:2F Connection request made
Jun 11 21:03:41 WLCEVENTD: eth6: Disassoc B0:72:BF:FD:13:2F Connection request fails at device 36 seconds later
Jun 11 21:03:45 dnsmasq-dhcp[790]: DHCPREQUEST(br0) 192.168.1.93 b0:72:bf:fd:13:2f
Jun 11 21:03:45 dnsmasq-dhcp[790]: DHCPACK(br0) 192.168.1.93 b0:72:bf:fd:13:2f Galaxy-S8 This is same IP address already in DHCP table
Which would seem to suggest, my device (Galaxy S8 : mac address: B0:72:BF:FG:13:2F)
a) Made a request to connect at 21:03:05 (Assoc)
b) The S8 was dropped at 21:03:41 (Disassoc)
c) A DHCP request for the S8 is issued at 21:03.45
d) And an IP address is return immediately thereafter.
Visually, on the phone, it is at this point that the failure message "Failed to obtain an IP address is received
If one goes to the Wireless log, we see an entry in the 5GHz table immedately after the connection request for the s8 with the IP address (.93)
This entry disappears when the disconnect (Disassoc) event is sent back
And if one looks in the DHCP table, there sits the S8 with its IP address, disconnected though it may be.

The normal course of events on a connection should have been
a) The assoc message
b) Immediately followed by the DHCP request
c) And the device shows a connected state/
And this is precisely what happens when the S8 connects to the 68U access point, except that the DNS request is handled by the 86U (as it should be).

And while maybe a case could be made that my S8 is defective
a) The S8 will nicely connect at 5GHz to any other router I put it to, including the 68U in the family room
b) Any / all devices that try to connect to the 86U (S8, tablet, PC) all fail to connect

And at the bottom of the Tools page, where it shows the count of connected clients to each channel, the Associated / Authorized / Authenticated counts all bump by 1 on a connection attempt, and then fall by 1 about 36 seconds later when the connection is dropped.

So, what seems to b going wrong is that on the 5GHz channel, a connection request will come in, it is verified (for it does fail immediately if the password is bad), but the router fails to make a DHCP request and pass the info back to the device. Then 36 seconds later, the router drops the connection with the device and shortly thereafter, does make the DHCP request - too late to do any good.
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