RT-AC87U keeps locking up

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smring78

New Around Here
Hopefully this helps somebody...

My AC87U would lock up and all clients would lose connection. I'm currently running the latest Merlin firmware (378.55). With a laptop cooling pad underneath my temperatures would still hover around:
2.4Ghz - 50C to 55C
5Ghz - 70C to 75C
CPU - 70C to 80C

The AC87U does not have vents on the bottom, so airflow from the laptop cooler wasn't making a difference. I have since removed the top shell of the AC87U, and built a cooler that sits above the router blowing cool air directly on to the processors and radios. The Cooler consists of two 120mm fans (It's a very crude design, and I will be working to refine it). I've been running this for 48 hours and had extremely stable performance. My current temperatures are:
2.4Ghz - 37C
5Ghz - 37C
CPU - 45C
 

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stinkybum

Occasional Visitor

Thanks, I'm going to try it out :) Adding a reboot scheduler is pretty much the definition of 'I give up, this device is a piece of crap'.

I tested the hggomes firmware and wow does it make a difference! Everything is a lot more responsive. I haven't tested it long enough to know if it solves the issue of locking-up problem. Unfortunately the source isn't available and no one really knows who hggomes is, so I wouldn't stick with this firmware.

It's a shame hggomes won't release his source because the wireless power increase is very useful. It lets me finally get the same coverage that I got from my Apple Time Capsule.

Hopefully this helps somebody...

The AC87U does not have vents on the bottom, so airflow from the laptop cooler wasn't making a difference.

There are vents at the bottom, they're at the sides, not in the middle. I have a fan blowing air into those vents underneath and it drastically dropped my temps. But I don't believe this latest issue with the router locking up is related to overheating.
 
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stinkybum

Occasional Visitor
I've had 21 hours uptime on the official Asus beta firmware 9.0.0.4.378_9110

It's still a bit too early to tell but I'm hopeful my problem may finally be solved!

I used to consider a few months as decent uptime for my Apple router. I consider anything more than 4 days as a major success for this Asus router.
 

wireless

New Around Here
I've had 21 hours uptime on the official Asus beta firmware 9.0.0.4.378_9110

It's still a bit too early to tell but I'm hopeful my problem may finally be solved!

I used to consider a few months as decent uptime for my Apple router. I consider anything more than 4 days as a major success for this Asus router.


Agree - 21 hours is too short ... This problem usually appears for the first time (in my configuration) between 2 and 3 days from total restart of all of my RT-N66U routers ....
 

Jong

Senior Member
I had 2 ac87s up for 100 days using 378.4950, but they have had real problems since. I'm hopefully, based on 9110, we are getting close to another good one though.
 

stinkybum

Occasional Visitor
So for those that said the problem is related to traffic analyser. I think you might be right.

I had nearly 2 days of uptime so I figured I'd try turn on the traffic analyser. After a couple of hours I noticed things were lagging a bit. After around 4 hours, the router locked up completely, requiring a hard reboot.
 

Stevemcclure

Regular Contributor
2 days up time here since turning off traffic analyzer off, is usually day 2 or 3 the lockups appear, so fingers crossed.

Now i don't know about these thing so am just chucking the ideas out there, but is it possible the traffic analyzer is filling the memory of the router up, and after 2-3 days it has a melt down and locks up?
 

Stevemcclure

Regular Contributor
4 days 16 hours now, this is the longest it's ever been running. Looking highly likely traffic analyser is the culprit here.


Sent from my iPhone using Tapatalk
 

stinkybum

Occasional Visitor
4 days 16 hours now, this is the longest it's ever been running. Looking highly likely traffic analyser is the culprit here.


Sent from my iPhone using Tapatalk

Same here, works perfectly but if I turn on traffic analyser it crashes after 2-12 hours. It seems the more traffic I have, the sooner it locks up.
 

RMerlin

Asuswrt-Merlin dev
Same here, works perfectly but if I turn on traffic analyser it crashes after 2-12 hours. It seems the more traffic I have, the sooner it locks up.

Can you check the size of /jffs/traffic.db after a while?
 

jslay

New Around Here
I have been running Traffic Analyzer. I get lockups every 3-36 hours on the regular. Brand new to ASUS gear and AsusWRT. Old linksys DD-WRT guy here.

Really loving this router (RT-AC3200) and the firmware, just hope turning off TA will solve my issues. Trying to run a server here that is constantly serving clients 24/7. Just turned it off, will be doing a router reboot and formatting jffs in a few hours when traffic dies down. Ill keep an eye on my uptime and report back.

EDIT:

/jffs# ls -la traffic.db
-rw-r--r-- 1 jslay root 3481600 Oct 3 22:00 traffic.db


Just checked my syslog server, nothing but DROPs and the regular start up mumbo jumbo after it locks up. Did have this kern disk_monitor: Got SIGALRM... but that was a solid 5 minutes before it locked up, and from everything I have found about this, it isnt a critical thing or abnormal. Just looks like a system event to possibly notify other daemons of an action happening.
 
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Stevemcclure

Regular Contributor
Same here, works perfectly but if I turn on traffic analyser it crashes after 2-12 hours. It seems the more traffic I have, the sooner it locks up.
Analyser still turned off and now been up for 5d22h.
I can happily live without traffic analyser, but for others who want to use it, then I suppose it's a good that this is looking like a software issue rather than hardware. So one would imagine that a fix in the firmware would be the solution, one for the experts to comment on tho as that's beyond my knowledge.



Sent from my iPhone using Tapatalk
 

jslay

New Around Here
Analyser still turned off and now been up for 5d22h.
I can happily live without traffic analyser, but for others who want to use it, then I suppose it's a good that this is looking like a software issue rather than hardware. So one would imagine that a fix in the firmware would be the solution, one for the experts to comment on tho as that's beyond my knowledge.



Sent from my iPhone using Tapatalk

I just passed my 36 hour mark. Haven't been able to do that since I had the router (3 weeks now), but I turned on TA right after I got it setup. Looking like TA is what is actually causing issues. This makes me sad because I was really excited about this feature. But I can live without to maintain stability.
 

Stevemcclure

Regular Contributor
Has anyone tracked the size of traffic.db over time?
I wouldn't know how to, I presume you would have to go into the jffs partition through ssl?
I am away all week, but will try and find out how when I get back, enable traffic monitor and try and to find the size of traffic db when it locks up.


Sent from my iPhone using Tapatalk
 

DanielCoffey

Regular Contributor
In Windows, puTTY is a good tool for looking at the jffs partition. Mac and Linux users can just use the terminal to ssh (although linux users can get a copy of puTTY too with "sudo apt-get install putty").
 
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DanielCoffey

Regular Contributor
Just to give you a data point, Merlin, I am a very light user of my AC87U (3x wired, 3x 2.4GHz, 1x 5GHz) and believe I have the Traffic Monitor off since /jffs/traffic.db is 0 bytes.

On a fresh reboot the router reported 73Mb RAM used. After 6d15h30m it reported 104Mb used.

I get occasional crashes on 378.55 once or twice a week where the router stops permitting traffic but lights are normal and a reboot is needed. Temperatures are Ambient 22C, 2.4GHz 43C, 5GHz, 70C, CPU 71C. The router is on feet to allow better airflow but is not actively cooled.
 

VANT

Very Senior Member
@DanielCoffey
try latest official fw from Asus. I also have "occasional crashes on 378.55 once or twice a week".
Now im on .9177, and still no crashes (before i test beta fw .9110 and also no crash).
IMO bug is in asus sources used in .55 FW
 

DanielCoffey

Regular Contributor
I will watch and report the allocated memory used over the next few days before I switch firmware - I have just rebooted today and managed six and a half days from the last reboot.
 

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