ZBT WE826 - Reboot automatically after an indefinite period

I installed the latest version of openwrt on a zbt we826 modem
But after a while (sometimes 5 hours, sometimes two or more times, sometimes more or less), it reboot itself
How can I fix this problem?

If the reboots are caused by kernel crashes you could try to retrieve the crash log via ssh cli cat /sys/kernel/debug/crashlog

It may provide a hint of what initiated the crash.

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thanks . i will check it now

and maybe check the system logs in between, see if anything unsavoury pops up

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The crashlog file does not exist in this directory after the reboot

May hardware be a problem?

So it is probably not the kernel crashing.

Hardware issue/failure that may not make into the logs is certainly one possibility.
Other could be overheating, issue with power supply (current fluctuation) or being syn flooded on the WAN - suppose you got syn flood firewall protection enabled?

If not already you could enable firewall logging in the WAN zone and watch the kernel log for signs of a potential syn flood.

I am not familiar really with the way how system logs are handled, meaning whether they survive a reboot? I use syslog-ng to retain a copy of the system log, on a separate drive, for that purpose (and logrotate for purging intervals).

can you explain me more about syslog-ng


I checked out
While 3 or 4 devices are connected to Wi-Fi, they will not be able to connect to the Internet after a while and no longer can be connected to Wi-Fi. And then after a while it resets itself. While Load Average is normal before this happens

tough call to remotely assist debugging without anything from the logs that even faintly would indicate of what is happening.

It sounds sort of Wlan channel getting jammed/stuck

Maybe take a step back

  • prior to the OS upgrade everything worked peachy with the same sort of network landscape/environment?
  • upgraded from which version to which version?
  • can you rollback to the previous setup and see whether still everything works, repeat the upgrade?

we use golden orbs rooter . but i use this before and i dont see this prblem
. how can get log from this ?
if wlan channel get jamm what are happen in os ? and why reboot device ?

The jamming is just a stab in the dark based on what you described. Had a quick glance at the device's specifications and looks like featuring 1 x 2.4GHz Wlan (supports 802.11bgn, up to 300Mbps)?

If there is some jamming the CPU could get overloaded and relieves itself from the load with a reboot. But again, this is pure speculation since there is nothing else really to go on.

But you did not respond to

i upgrade with 18.06.1
yes i can . and check it by previous firmware
but i want find this version problem . how can find solve of this jamm problem ?

My humble suggestion would be to take a first step by rolling back to the previous installation and give it say 12 hrs, with the same sort of workload (client traffic), just to be absolutely certain that it is not some sort of hardware fault.

It would be rather conclusive if it works all peachy with the previous version but not with the upgrade.

May I also suggest not to get too focussed/fussed on the jam thing? Could be easily just some setting or something gone awry during the first upgrade and things work out fine on the second go.

You could ask this question in the golden orbs rooter forum.

Maybe the mt7620 and mt7628 drivers have problems with this modem?
I used these packages for a wireless driver

You upgraded from the Golden Orb ROOter provided image/distro to vanilla OpenWRT?

I am not familiar what sort of patches they put on top of OpenWRT. Maybe you just need to wait until they get around to release a new distro image based on 18.06.4.

These drivers are also used in the latest openwrt version
I want to investigate and fix the problem. In general, this is not the difference between the two

If you are sure. I suspect that the downstream repo patches OpenWRT and utilizes particular settings which are gone when upgrading from GOROOter image to OpenWRT image.

I would not know whether GOROOter is contributing their patches to upstream development or not.