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RT-AC86U Rebooting over and over

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OK. It was just a thought. I don't have a Xbox. I thought it might be flip-flopping between the wired and wireless connections.

I seen reports from people that say they've had issues with the Xbox's network once it's gone into standby. I don't know the details.
Thank you for the suggestion. Yeah, my Xbox rarely turns on remotely, even though that is an advertised feature that should be able to be done from multiple apps. Either I have a lemmon in regards to the NIC, or there’s something about my router(s) it doesn’t like. It acted similar with the AC68R that was in the place of my now AC86U.
 
I have rt-ac86u with merlin and been running for 3 days + straight without any reboot

My up time is 24 days and I use 2.4 and 5Ghz bands on my RT-AC86U on Merlin 384.5
 
Mine is still randomly rebooting but so random (a week or more apart) I cannot pin it down to anything. System log does not appear to show anything. When it starts up again the log is full of a date of February 13 at 16:00 and the last entry prior to that date, i.e. the date that it crashes, the last entry can be hours before it crashed so nothing to glean from any of that. Could this be hardware issue? After reverting to factory defaults and ASUS firmware I reloaded Merlin 384.5 and this is what is on it when it has been crashing.
 
I have updated from 384.4_2 to 384.6 and I started experiencing random reboots from matter of hours to days.
Tried to downgrade back but the issue seems to persist.
The logs doesn’t show anything other than booting up.
Anybody managed to solve the issue?
 
I suspect it is either memory related or the device freaks out when another device connected to its switch ports becomes active. My rationale for memory as the cause is that I notice that if the free RAM starts to show as lower than normal like less than 15% free (mine is currently using 77%) that it reboots. But I have no hard data to prove this.

The other thing that I know for a fact causes it, is when I turn on my Apple TV if it has been asleep for a day or two it will sometimes cause the RT-AC86U to restart. Then last night, we have another dedicated VPN/wifi device connected to one of the RT's LAN ports for my wife's work, I power cycled it before her shift and this caused the RT-AC86U to reboot. I was going to reboot it (RT) next just to make sure she didn't lose her connection while working but I saw the lights go out and sure enough it rebooted itself. So is this a hardware issue? Or does the switch part of the device need a firmware upgrade?
 
I did not have this issue when I was on 384.4_2 with more than 2 months uptime.
No new devices have been added to the network so far.
The memory utilization on the 86u have always been 90+% without any issues.

The issue only started when I flash to 384.6.
And the same, I can't see any error logs prior to the booting up logs.

I tried to flash back 384.4_2 and 384.3 and the random reboot still persist. (it rebooted as well during 3am night when nobody is using)

Now I have flash to the latest stock Asus 3.0.0.4.384.21140 firmware and having 2 days uptime.
It might be the advance configuration as mentioned by madfusker but i'm not sure what is causing it.
 
So far using the stock Asus 3.0.0.4.384.21140 firmware and having 21 days uptime.
Same HW ver 1.5 and 2018 production.

I'll wait for the merlin 384.7 stable release before trying to flash again.
 
Hi all - I just got an AC86U a week or so ago, upgraded it to stock Asus FW 384.21140. Just this morning it has rebooted itself twice within about 10 minutes. Anything in particular I should be looking for in the system log? Normal router mode, nothing connected to USB, two devices connected to LAN ports.
 
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It is my guess that it is related to the switch function of the router, i.e. the LAN ports. Mine will often reboot after I wake my Apple TV that is connected to one of the LAN ports. Also it will reboot if another VPN Wifi device that my wife uses for work that is connected to LAN ports. If that device is restarted it will cause this router to reboot. This really sucks for such an expensive wifi router. We rely on it for our work and often critical functions are interrupted mid stream.

Merlin, ASUS, anyone? Is this a known issue, is there a firmware update coming to fix this? If not, can anyone recommend a stable device to replace this crap with? It is just too unreliable for our environment.
 
It is my guess that it is related to the switch function of the router, i.e. the LAN ports. Mine will often reboot after I wake my Apple TV that is connected to one of the LAN ports. Also it will reboot if another VPN Wifi device that my wife uses for work that is connected to LAN ports. If that device is restarted it will cause this router to reboot. This really sucks for such an expensive wifi router. We rely on it for our work and often critical functions are interrupted mid stream.

Merlin, ASUS, anyone? Is this a known issue, is there a firmware update coming to fix this? If not, can anyone recommend a stable device to replace this crap with? It is just too unreliable for our environment.
Complete guess, but is spanning tree protocol enabled under LAN - switch control?
 
Complete guess, but is spanning tree protocol enabled under LAN - switch control?
Yes it is. Do you suggest disabling it? I have VLANs so that I can bypass using Centurylink modem and just bridge into my network on their VLAN 201 into this router and 4 other switches in my network that are configured to separate that VLAN from the LAN traffic. It has been like this all along even with my older RT-AC66U and it never had this issue.
 
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Worth trying if you don't have a complex network that rely on it
Ok. It has now been up 44 days and no random reboots such as when waking apple TV or other connected devices. It appears that your suggestion of turning off spanning tree protocol is the fix.

But why would that have been the case, that disabling it fixes it? I have VLANs configured on my 5 switches (the ASUS being one of the switches).

Thanks Jack Yaz.
 
Worth trying if you don't have a complex network that rely on it

Interesting idea, thanks Jack.

I too have had this same issue and thought it was the 4TB HDD attached to the USB 3 port taking up too much of the RAM, but after using the “sync” function to clear the memory regularly and not using the drive at all, it still kept happening.

After going on holiday for 2 weeks with a couple of devices on and not having a single crash, I came back and as soon as our phones joined the wireless, it crashed, which steered me away from the HDD being the problem.

So... naturally... it’s time to test...

My parents have the same router and theirs ran flawlessly for months with no issues having many wired and wireless clients (including EoP) after immediately upgrading it out of the box to Merlin 384.5.

On that same holiday, I connected a 500 GB USB 2.0 HDD to their router, which then began crashing regularly.

After getting Mum to unplug the drive, it still continued crashing regularly, even though, up until connecting the drive, it ran flawlessly.

Both aforementioned drives were running an EXT4 file system, which I thought would be more “native” to the Linux box.

I have now returned to using the Asus stock firmware on both modems (and no USB drives on Mum’s) until the next Merlin release, when I will test it on my router first before burdening the family with it again.

I’m now testing out EXT3 USB drives on stock firmware and it seems to be running fine. (Stock firmware won’t format a drive to ext4)

Kinda sucks though, as I had a TAP VPN running between the two houses, both sharing the same subnet with DHCP doing half the range each side, which allowed iTunes music sharing and file sharing to run very nicely indeed. I could even Airplay and Mirror screens etc.

That’s now disconnected temporarily because of course, Merlin allows one to drop the DHCP Layer 2 broadcast messages over the VPN using a firewall-start script so clients on each side acquire their IP from their own router and still use the local router’s internet connection.

Any ideas on why connecting a USB drive would affect/link to TSP?

Looking forward to when it gets resolved.
 
@DBMajor in case you missed my last reply... I started this thread and it was not until Jack Yaz suggested turning off Spanning Tree Protocol that the issue was resolved. Therefore, for me, that fixed it and I have not had that issue ever since I TURNED OFF SPANNING TREE PROTOCOL. Not sure why but that fixed it in my case. I have a few VLANs running on my network so could have been related to that but TURNING OFF SPANNING TREE PROTOCOL was the solution for me. so, in cased you missed it, TURN OFF SPANNING TREE PROTOCOL and see if that fixes it, as it did for me.
 
Hello ...
I know the topic is old but I have the same problem with my Router Asus RT86U - Made in china 2019 - revision 1.5 - with Merlin FW 384.19, FlexQos , amtm 3.18 and Diversion plus USB 8GB - ext4.
The weird thing is very funny in a way. The Router reboot himself after 4 days sharp for about 10 seconds and after reboot everything works fine. What bother me is the fact, HE do that in the middle of VOIP or something important for me in the middle of the day or morning when I need constant connection. I try to associate some activities or connections when I do something "special" in my network but was not very clear if something have some influence on that. The last advice read here is disable STP ... on me is ON ... but I don't know if it's fine for me on my network arrangement. I put an attach here to advise me if I can try to disable STP ... if STP could be the problem ....If are any info I can provide, please let me know.

Also I want to mention about devices on my network ... are 6-10 wifi devices connected all the time - 4 smartphones, printer, vacuum cleaner , washing machine, Ipads ...

Thank for all advices to come:)
 

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My rt-ac86 used to reboot by itself every 5 to 6 days regardless of firmware version, in the end it was like a routine , until I disabled all the TrendMicro stuff, since then it never has rebooted by itself.
 

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