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Bug? Asus RT-AC86U running 386.2.6 - Total loss of 2.4 GHz Wi-Fi after some days

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Konsti

Occasional Visitor
Hello to all forum members, first of all my warm thanks to the team behind the AsusWrt Merlin releases all this time. Apologies if accidentally posted in wrong sub-group (I did check carefully).

I very recently purchased an Asus RT-AC86U router and almost immediately updated it to the latest AsusWrt Merlin 386.2.6 firmware; after factory resetting, I enabled it for my fibre-operator with minimal changes for my home use.

I disabled the Smart Wi-Fi Connect as it was not working with some home cameras and smart-plugs, and thus created a typical dual Wi-Fi network at 2.4GHz and 5GHz respectively with default settings (except SSID name and password, obviously).

However, I notice that some days after the last router reboot, the 2.4GHz network ceases to exist (!) and only 5GHz continues to be detectable; I noticed this as my smart-plugs starting blinking. When trying to find it with my iPad, it is no longer there.

It just happened again after 5 days and decided to register here, and post my problem. The router itself is thankfully accessible (including Asus own smartphone app) and before rebooting it to solve this, I wanted to post here and ask what kind of logs (and from where, and if sanitized) would make sense to provide and give an idea what is wrong...

The router does not seem to be under heavy traffic or use when this happens, and the number of devices is not so high to justify the 2.4GHz going down. Also, there is no Guest network enabled nor any AiMesh set up.

I worry that this will happen again when I won't have access to the router and thus no smart-plugs or home-cams working :(

Is there a way to totally reset the Wi-Fi settings to defaults, without resetting the whole router again?

N.B. Accesing the CLI and ran service restart_wireless did not seem to have solved the issue, clients can't seem to connect to this 2.4GHz wi-fi (saw it in this post).

On some other website there was a mention of running /sbin/restart_wireless but that did not yield results, earlier (not sure if it's even the proper way to do it, for this latest Wrt firmware).

P.S. In the Professional section I had only lowered a little the TX power to "Good" and nothing else; would this be the culprit? Set it back to "Performance" default but that didn't help either.

P.S. Decided to perform a factory reset again (via UI) ; just set the basic router settings (vendor class, admin user, Wi-Fi details) but having trouble again with 2.4GHz. It doesn't seem detectable from devices. For the love of mine, I can't figure out what is wrong. A hard-reset would help?


Thank you again.
 

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On my ac86u if I leave 2.4Ghz wifi on auto channels it sometimes stops working because automatically sets channels weird like to 9. If i manually set it to 1/6/11 I never have issues, 1 month uptime on some devices.
Asus firmware is very buggy. Always was, and always will be. Another Issue I once had was by changing a lot of settings in wifi professional tab sometimes the webGUI would show adicional settings and if i change one of those settings wifi would just stop working altogether. :rolleyes:

The other day I tried to assign manual IP to a printer and I couldn't connect to the Internet on any device until I removed it. dnsmasq went to shiit, and I don't even use unbound anymore. Only script I use is diversion.
 
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Thanks @askan7 I did a hard-reset again and I cannot get any devices to detect the 2.4GHz network, this is nuts, it's like it doesn't exist.
I did not expect Asus firmware to be that buggy... spent a fortune for this router, reading this is rather disappointing. Should a factory reset at least work out-of-the-box? Despite the reset (soft and hard) the router still doesn't show any 2.4GHz client connecting at all, I have no idea what to do next.
 
Thanks @askan7 I did a hard-reset again and I cannot get any devices to detect the 2.4GHz network, this is nuts. I did not expect Asus firmware to be that buggy... spent a fortune for this router, reading this is rather disappointing. Should a factory reset at least work out-of-the-box? Despite the reset (soft and hard) the router still doesn't show any 2.4GHz client connecting at all, I have no idea what to do next.

Even with factory reset, If my router decides to set wifi 2.4ghz to some in-between channel my devices can't connect to it. But this is in every firmware, since 384. This router is good in performance, but I think i'll be my last broadcom based router. My next router will be something that allows to install openwrt.
I also have a few small issues with cakeQOS that seems related to the way cake is implement, that happens with my ADSL connection and also my LTE connection. Soo it's not my connection. Cake works ok, but it's not perfect on these routers even tought it gives good results on DSLreports(A/A+) and other tests.

Also the ac86u on v386 has very high cpu usage issues while transferring files from USB, and with VPN it seems. I think Asus fixed this on latest release, need to wait for RMerlin to merge it with 386.3.
 
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First, I would suggest that you install something like inSSIDer on your laptop to look for possible radio interference from something nearby. At the least, I would strongly suggest (as did askan7) you stop using 'auto' for channel selection. Choose a channel (based on inSSIDer analysis).

I'm gonna bet your issues are interference related (like maybe a microwave oven??)...
 
Thanks for your feedback, I will be setting each frequency to a specific channel and bandwidth and report back.

For the moment, a rater n00b question as I am not totally aware of the specs: this router has a single Broadcom chipset for both Wireless types, correct? I am trying to exclude any possible hardware fault to be honest.

Some clients see the 2.4GHz network but WPA2-Personal credentials aren't accepted (iPhone 4s says "incorrect password"!) so not sure if I should also switch to Legacy or N type, has it occurred to you at all that SSID password is not accepted despite being the correct one?

Thank you again (and to thin that I sold my OpenWrt Asus RT-AC58U to get this one)

Update: 2.4GHz channel 6 seems to be free in my building, no interference. Still issues!

Update: Disabled 5GHz on purpose. Rebooted. No clients connect at all. This is madness. I am getting desperate.
 
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Reverted to Asus firmware 3.0.0.4.386_42643 and did yet another Factory Reset. Still nothing. With basic stuff such as admin username/password, vendor ID for ISP and SSID details, no device can connect to 2.4GHz. The DHCP list is totally empty. Could the Asus be defective? Any ideas? My iPhone 4s says "wrong password" when trying to connect :confused:


How can I check that the actual 2.4GHz wireless part of the device is not having hardware issues? Any ideas welcome :(
 
Hi @explorer200 thanks, can you elaborate please? Does this router use a single-Broadcom chipset for both WiFi networks (frequencies)? Is the chipset known to be buggy or the router model? I just contacted the vendor for its replacent. Should I ask for a refund?

So this is not some driver problem as I had hoped, nor some funny flash region that got corrupted, perhaps?

Thanks @L&LD I will read these tonight and comment back. My first feedback is that after doing again (earlier to this post) the dedicated reset-button action (rear panel) and then seeing that the 2.4GHz doesn't work after the quick initial re-setup, I turned the router off. Later turned it on and the wireless in question unexpectedly worked (actually got some notification on my device). No idea what happened (but was not in the Setup Wizard mode) and after a soft-reboot, situation seemed "normal" but I don't trust this router.

I will report back, but this is nuts.
 
Is the chipset known to be buggy or the router model?

Many AC86Us failed in first 2 years of use perhaps due to poor thermal design and inconsistent quality of materials used.


2.4GHz IC is BCM4365E (3x3 b/g/n), 5GHz IC is BCM4366E (4x4 a/n/ac). Failing 2.4GHz is/was a common issue, in my opinion related to near hot spot on the other side of the PCB, resulting over time in IC solder micro cracks. High thermally stressed RoHS electronics suffer form this often. Re-flowing the IC restores the functionality, but the router may fail again after. Many AC86Us failed due to poorly implemented reference circuit around one MT3125 step-down converter. This is the LAN4 LED death, discussed largely in tech forums.

 
Thank you @Tech9 for your technical feedback. The router has only been used like 15 days and in normal room temperature conditions and not heavy use; hence why I had selected the TX power to lower setting (my flat is small, really). Would this ease a little the heating situation i.e. setting to 50% TX rate?

I cannot believe that a model that I considered a successor to RT-AC68U and found on "offer" would suffer from such issue :( It is a little late for refund I think, the replacement was eventually decided from the vendor's side. I can push for a refund if done tomorrow morning...

Do you think that Asus may have fixed the issue in some V2 or V3 of the router, or is this an overall issue for this model? I admit I have not done extensive technical search, never anticipated such problems with such expensive router... The rear sticker writes Production Year 2020 in China, so I would say it's rather new... Thank you all.
 
Do you think that Asus may have fixed the issue in some V2 or V3 of the router, or is this an overall issue for this model?

As far as I know all AC86Us are hardware revision 1.5 and no changes were made to the design. Changes to materials used are possible - better thermal transfer pads, better solder and some of the passive components. Statistically most affected series were manufactured in 2018, but I see folks with 2020 routers reporting overheating issues. I'm seriously in doubt Asus is going to fix any further 2017 model AC router. AC68U situation was different - all were AC routers in AC era. Now the focus is on AX.
 
Would this ease a little the heating situation i.e. setting to 50% TX rate?

Possibly, but I wouldn't trust this router in a long run. I don't know what your requirements are, but if you ask me - for your small apartment an RT-AC66U_B1 router is more than enough. It's the latest AC68U variant, runs the same software. It's a stable and trouble-free AC router. I would run 384.18 Merlin on it with few additions only or stock Asuswrt.
 
Thank you for your valuable advice, it is greatly appreciated. I was under the impression that such expensive routers (see "Gaming"...) do get through enough stress and strain during design so that, when released to the market, can stay alive for 4-5 years; but this one proved otherwise (and instead of removing from sale, Asus seems to continue manufacture/sell it?)

In any case, the 2.4GHz Wi-Fi network re-appeared last night and this morning disappeared again. So the problem is there. I am packaging it for sending it back, and had a strong argument in order to be refunded.

I will thus look out for offers on RT-AC66U_B1 instead, which, as you wrote, is a variant of the rock-solid RT-AC68U that I hope has equal features besides the enclosure differences.
 
Before you go for a different router model:
Why do you need Asuswrt-Merlin on your router? (there is no OpenWRT Merlin)
 
Good day (and apologies for "OpenWrt Merlin", I corrected my OP) I am looking to replace the router of the fibre provider here in FR and add some more powerful features like VPN such as OpenVPN Server or IPSec to connect to my OpenMediaVault NAS from the outside, and also explore plugins on the Asus etc. that may not be possible with normal AsusWrt (I think). Moreover, I trust that "Meriln" is more stable in some aspects as it seems to be more maintained, no?
So nothing fancy for now - just explore the extra potential. I was just looking for a solid router and since RT-AC68U still sells in too high of a price, I thought of getting the RT-AC86U that was found on offer at a "decent" price (and the idea of getting the RT-AC66U_B1 seems equally good, found "like new" as a warehouse deal).
 
OpenVPN Server or IPSec to connect to my OpenMediaVault NAS from the outside, and also explore plugins on the Asus etc.

AC66U_B1 is a good budget router, but AC86U is much better for VPN and scripts. It has CPU with AES support and 512MB RAM. One defective AC86U doesn't mean all are defective. It fails more often statistically, but many folks around use AC86U with no issues. You decide what to do.

I trust that "Meriln" is more stable in some aspects as it seems to be more maintained, no?

Asuswrt-Merlin gives you more configuration options. I don't use Asus routers and I can't comment on stability. My AiMesh 2.0 test setup worked better on stock Asuswrt. My advice - start with Asuswrt and see if it works for you. If you need something more - switch to Asuswrt-Merlin.
 
Thank you again @Tech9 for taking the time to reply and for this technical exchange. You are correct about not all being defective... but perhaps I considered the RT86U an overkill or was let down, disappointed. I got my RT66U-B1 now up and running; indeed I miss VPN with IPSec, PPTP is no longer supported by macOS but since OpenVPN seems to be present, I will manage. But our exchange was very helpful and provided better insight and a reminder to better research next time... (for me)
 
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