AX88U Merlin 386.x and 388.1 random WAN disconnects mostly without relevant log entries

[Viktor Jaep]

Just wanted to report ever since downgrading the issue still persists.

It happens on the hour EXACTLY. When it happens the router's admin page is also no longer responsive, nor will it load.

Could you please post a list of all the different cron jobs that you have running?

 

[ColinTaylor]

Question for those in the know... how does your standard router (or AX88U) determine if the WAN link is down? Is there actually a link up/down kind of alarm that sets it off, or is it sending some kind of regular heartbeat signal out, and if it doesn't get a response, goes down? Just wondering how this truly functions?

wanduck polls the condition of the WAN(s) approximately once every 5 seconds. One of the things it checks is the "operstate" of the interface. It also checks the value of wanX_state_t. Either of these may signal that the link is down ("Interface is unable to transfer data on L1, f.e. ethernet is not plugged or interface is ADMIN down").

 

[BigScream]

Could you please post a list of all the different cron jobs that you have running?

Just the system defaults. I really havent used any of the adv. features besides what the GUI offers (im lazy).

 

[DocUmibozu]

I manually forced this error to occur and this is what I got in my AX88U log. By the way: can you also force it to happen? I do this by downloading huge test files and wait for a few minutes and it will surely disconnect.

My disconnection is unrelated to traffic.
The first time I was listening a song on spotify.
The second and third time network was idle, I noticed it only by the logs.
By now 14 hours passed and it seems stable….
I’ll update tomorrow in the morning.

 

[JohnDeere]

My disconnection is unrelated to traffic.
The first time I was listening a song on spotify.
The second and third time network was idle, I noticed it only by the logs.
By now 14 hours passed and it seems stable….
I’ll update tomorrow in the morning.

Did you find anything relevant in your logs? My disconnections already occur a dozen of times within an hour. I still haven't done a full reinstall yet, hoping to understand the cause...

 

[DocUmibozu]

Did you find anything relevant in your logs?

Nothing.
And I haven't experienced any more disconnections.
So, in my case, it was a strange but temporary glitch.

 

[JohnDeere]

Nothing.
And I haven't experienced any more disconnections.
So, in my case, it was a strange but temporary glitch.

Thank you for the feedback. This has happened to me before as well. There were days, almost weeks when no disconnections haopened. Then it started again - at least in my case. I hope you won't have this problem anymore

 

[Bodin Praphanthongchai]

I have extactly the same issue for the last two months. I thought it was RCN. I'm using Arris SB8200 Bridge on AX88U. They sent the techinician to check and try to fix it couple times but still can't solve the issue. So, I switched to Xfinity 2GB and got XB8 modem with 2.5GB port. I setup as bridge mode connect to AX88U and the problem still exist ( randomly disconnected ). Then 3 days ago USB 2.5GB was arrived. I plugged in the USB port next to the WAN port and use it as USB Modem 2.5GB connected to XB8 Modem. Untill now it still stable never disconnected.

I think my WAN port might having an issue because it is a bit loose and playing a bit. I'm not so sure in your case. Anyway, I'm still waiting for GT-AX6000 to arrive I can get the most out of multigig speed. Hope you can solve your issue soon I can feel it was frustating.

 

[JohnDeere]

I have extactly the same issue for the last two months. I thought it was RCN. I'm using Arris SB8200 Bridge on AX88U. They sent the techinician to check and try to fix it couple times but still can't solve the issue. So, I switched to Xfinity 2GB and got XB8 modem with 2.5GB port. I setup as bridge mode connect to AX88U and the problem still exist ( randomly disconnected ). Then 3 days ago USB 2.5GB was arrived. I plugged in the USB port next to the WAN port and use it as USB Modem 2.5GB connected to XB8 Modem. Untill now it still stable never disconnected.

I think my WAN port might having an issue because it is a bit loose and playing a bit. I'm not so sure in your case. Anyway, I'm still waiting for GT-AX6000 to arrive I can get the most out of multigig speed. Hope you can solve your issue soon I can feel it was frustating.

Yes, it is very very frustrating. Thank you for your post, it is interesting. Did you start experiencing this issue after a "dirty" upgrade? If so, was it fine before the upgrade?
Did you check your modem's log for lan cable disconnected errors?
I'm glad your system is fine now.

 

[JohnDeere]

Just an update: today the SMB Samba server stopped working on this AX88U. I tried restarting it several times, restarting router, but nothing helped. I had to revert back to Merlin v 386.8 and reload the saved settings related to that version. First FW update was unsuccessful. The second time was OK, and the SMB server was working again. Now I'm on 386.8 with working Samba.
Disconnections still happen randomly. However I keep getting a brand new error in logs:

Dec 21 15:47:37 RT-AX88U kernel potentially unexpected fatal signal 11.
Dec 21 15:47:37 RT-AX88U kernel CPU: 1 PID: 21544 Comm: dcd Tainted: P O 4.1.51 #2
Dec 21 15:47:37 RT-AX88U kernel Hardware name: Broadcom-v8A (DT)
Dec 21 15:47:37 RT-AX88U kernel task: ffffffc02f02a0c0 ti: ffffffc020e08000 task.ti: ffffffc020e08000
Dec 21 15:47:37 RT-AX88U kernel PC is at 0xf72d939c
Dec 21 15:47:37 RT-AX88U kernel LR is at 0x1dce0
Dec 21 15:47:37 RT-AX88U kernel pc : [<00000000f72d939c>] lr : [<000000000001dce0>] pstate: 600f0010
Dec 21 15:47:37 RT-AX88U kernel sp : 00000000ffe7baf8
Dec 21 15:47:37 RT-AX88U kernel x12: 00000000000a2050
Dec 21 15:47:37 RT-AX88U kernel x11: 00000000f65ff024 x10: 00000000000a23c4
Dec 21 15:47:37 RT-AX88U kernel x9 : 00000000f65ff61c x8 : 00000000000a287c
Dec 21 15:47:37 RT-AX88U kernel x7 : 00000000f65ff654 x6 : 00000000000a2876
Dec 21 15:47:37 RT-AX88U kernel x5 : 0000000000000000 x4 : 00000000f65ff600
Dec 21 15:47:37 RT-AX88U kernel x3 : 0000000000000000 x2 : 00000000ffe7bad4
Dec 21 15:47:37 RT-AX88U kernel x1 : 000000000007d72a x0 : 0000000000000000

I wonder if this helps tracing WAN disconnected errors...

 

[CajunFeather]

I had the same issues where my internet would suddenly drop on my RT-AX88U daily, weekly, etc.... it was random and never patternistic... I finally kept reading that others had rolled back their firmware to 384 and said "why not let me try it"... I'm not going on 8 days of internet staying online straight with no hiccups or reboots so there definitely is something within the 386/388 code that was causing the issue.... i have a 1Gbps Fiber line that has been consistent since day one however can't say that much for my router.