RT-ac66u reboots like crazy

[smcb]

This has been driving me crazy for several months now. I have an RT-AC66U, and I have tried the latest firmware (every time it is released), and I have tried all the latest Merlin firmware. I have not yet tried dd-wrt on it, but I'm considering it.

The router just reboots out of the blue, and often (like every 90 minutes or less). I have sent it in to Asus and had it replaced 3 times now, so I know it isn't the hardware. It seems like a device on my network is causing it, but I have not been able to isolate a single device that is doing it.

I even replaced my cable modem thinking that was the problem.

Any suggestions how to cure this problem? I love the Asus router, but hate that it does nothing but reboot so often.

HELP!

ps... I have also tried different power supplies. I have 3 of them from Asus.

 

[mteicher]

Hello,

Many years ago I was monitoring some unix servers for uptime and availability of services. One of these monitoring programs was causing a server to reboot at random. Needless to say that unix flavor came out with a new version rather quickly.

So if you are doing some kind of monitoring you might wish to stop it and see if that is the culprit. Even tho its highly doubtful what I experienced is the cause of your issues.

 

[smcb]

nope, no monitoring. It will just suddenly reboot, and we know it because the laptops suddenly disconnect from the wireless, it takes a minute or so to come back up, then I go to the System Log on the router and find the up-time has reset.

I realized tonight I do have one constant that has been on my network through all my tests - I have an SPA-2102 phone adapter on the network. It is in bridge mode (so it isn't doing any routing), and I have always had it connected because we need our phone service. I'm wondering if somehow this box is sending some sort of data that the RT-AC66 doesn't understand how to handle and it crashes.

Maybe tomorrow I will see if I can disconnect it for a few hours and see what happens with the Asus. Maybe it is time to get a new phone adapter.

 

[mteicher]

Hello,

You say you look at the up time as the indicator the system rebooted. Hope you also you have looked at the system logs? You might look at what ports your phone adapter connects to the router with and set up logging if that's possible.

 

[smcb]

There is nothing in the logs on the router (it has rebooted 3 times tonight since I made the first post). There are the log entries after the last time it rebooted, then nothing for a period of time, and then new log entries with the date/time reset.

Maybe I will see if I can set up a wireshark trace and see what I can capture leading up to a reboot.

 

[mteicher]

I would be interested in what you find out.

 

[RMerlin]

Two things that come to mind:

1) Disable HW acceleration, under LAN -> Switch Control. Some ISPs have issues with it.

2) Look for a potential power issue. Is the router on the same electrical circuit as any other device that can potentially draw a lot of current (such as a laser printer, for example)? Might not hurt trying a different power bar while at it.

 

[smcb]

So last night I ruled out the voip adapter. turned it off for the entire night, and the asus router still rebooted every couple hours.

today I have disconnected everything else - satellite receiver (which was replaced with a different model recently - dish hopper - it was rebooting before the hopper was here), xbox one is now disconnected, both printers turned off, cell phones on wifi are off.

The only thing left is my own laptop. So I'm going to see if it reboots again now.

I have tried turning off the hardware acceleration numerous times before, it makes no difference.

 

[Engineer]

Have you opened up the unit (assuming it's not under warranty) to see if there are any swelled or leaking capacitors? I have seen many types of hardware (including TV's, motherboards, etc.) exhibit this behavior because of a leaking/bad capacitor.

How old is your router?

 

[smcb]

Asus has replaced my router 3 times now. Each one suffers from the same problems from the moment I put it on my network. This one just arrived this week.

I have been suffering through this problem since april, and this wasn't a cheap router. Today, I shut off everything except my own laptop. The router still randomly rebooted.

So I shut down my laptop, and turned on a different laptop. And it still reboots randomly with only a single device connected to it.

Yet I can swap in a cheapo belkin router I bought for $30, and it works perfect. Of course it has none of the features that the AC66U has (which is why I bought the asus).

I'm just so frustrated because this has to be a firmware problem, yet I seem to be the only person suffering from it.

 

[L&LD]

Would be surprised if it was a firmware issue with only you suffering.

What settings do you change from defaults? If you leave everything alone after a reset to factory defaults, do you still experience the same thing?

What network or other related settings do you change on your devices?

With a few customers with this exact router and relying on 24/7 operation, I have not seen anything like what you describe here.

 

[john9527]

First thing I would try is to change your modem to router cable....Cat5e minimum, Cat6 better.

Next, have you checked the modem logs for problems/signal levels? Bad or marginal signal levels can cause the modem to go into recovery and the router to reboot.

You may want to browse through this thread for some things to look for.
http://forums.smallnetbuilder.com/showthread.php?t=19041

 

[ml70]

My AC66 sometimes was stuck in a boot loop when it was new, only changing to Merlin fw solved it. Had something to do with the ethernet cable as with the wan cable unplugged the bootloop would never happen.

Did you clear the nvram between fw flashes?

mtd-erase -d nvram && clear nvram && reboot

 

[smcb]

I have tried different cables between the modem and router, the cable modem is not rebooting when the router reboots. There is nothing in the router logs prior to it rebooting.

I have tried the router with all out of the box defaults, and it still does it.

I've been suffering through this since april, and the router has been replaced with different units with different serial numbers 3 times.

With no devices attached, it still reboots occasionally during the night. I even replaced the cable modem with a newer one (Surfboard 6141)

 

[Wisiwyg]

Overheating? Do you have the router in a hot cabinet or closet with no ventilation? Have you tried to put a small fan on it?

 

[Cleaved]

I have also been having this same issue, and I am curious to see if anyone has found a solution.

I got the router back in February, it had constant disconnects (apparently rebooting just like the issue in OP). I put my old crappy router back on, and it worked flawlessly. Sent the new router to ASUS for repair, they sent it back damaged, finally got it back this week.... STILL has the disconnect issue. The logs still show a reboot.

Did OP ever find a solution? Was yours sitting in a spot that gets hot and might cause a reboot? I'm curious to know, since mine is in a closet (central connection to built-in home network wiring/cable).

Thanks for any help. This has been an ongoing for nearly a YEAR, and I am really at my wits-end with ASUS tech support. Most of them are uncaring jerks, with only a few diamonds in the rough.

 

[Cleaved]

I can confirm that this issue is due to heat. I have put a small fan on my router and have had constant up-time with zero reboots for weeks now. Before, I was having a reboot occasionally during the day and constantly when under heavy load at night.

I will be getting a laptop style cooler fan to sit it on that might use less power than the small fan I have on it currently.

I hope this helps anyone else who was experiencing this exact reboot issue. I had sent mine back to ASUS twice with no fix, and a simple fan did the trick (FINALLY!).

 

[lucassp]

I also experienced random sessions of continuous rebooting (like once every 2-3 mins), which stopped after pulling out the WAN cable. After inserting the WAN cable, the router started rebooting again. Leaving the router off for a few hours helped and no more reboots have been encountered for a while. The reboots came back randomly, between a day and a month.

We checked the WAN cable which was 0.5m long between the optical fiber media converter and the router, but nothing was wrong with it. I wrote about it on the ASUS forums but nobody helped. The ASUS support staff gave me the standard solutions: latest firmware, check cables, etc. When we were about to give up and order some really expensive professional solution, ASUS released 3.0.0.4.374.4561 21/02/2014 and our issues went away. Hopefully forever.

 

[jfreemanak]

I have a similar issue and it is getting old fast. Last July, it begun when I upgraded to the latest firmware (1123). After reverting back to an old firmware, my router was stable. I just updating to the latest firmware (followed by a hard reset), and now the router is constantly resetting.

I know it has to be the firmware, because when I load DD-WRT or Tomato, the router works flawlessly (runs for weeks and weeks without a problem). However, I like the features of the ASUS firmware.

The logs are no use because they are new every 10-15 minutes. Any ideas?

Cheers,

Jared

 

[iLoveLobster]

I'm having the same issue but my restarts are longer, maybe every morning. It may be more because I'm not home all the time, but I'll be taking a closer look.

Someone has suggested on a different thread that it may be an AC adapter issue:

http://forums.smallnetbuilder.com/showthread.php?p=162328#post162328

I have mine plugged into a UPS and I am going to try and single this out by plugging the existing adapter into wall instead. Other than that, I'm going to try a different AC adapter and see if that works.

I've never had problems with the router up until 2 months ago with this issue. Tried a number of firmware especially factory defaults, still the same issues.