Ah, did not notice the login entry. In fact I logged in just after the crash, not before.
I thought the same, but it was suggested to do so, so I did. I guess the log might offer more relevant details.
This are the log entries just before the "crash". I think it is what caused it or at least the symptoms of it. I had a short Google search and there have been similar problems with disconnects "due to excessive missing ACKs" on other router models, but not sure whether this is the same problem here or has a different root.
Sorry, but no.
Logs do not survive crash & reboot, as logs are held in RAM in order to avoid flash writes. You will not get any useful information from new logs, which are totally about after-reboot events.
The timestamp that misleads you, is wrong. Your router has no real time clock, so it loses time after reboot. The router uses the date/time of the most recent file on /etc as an approximation of the best known last date/time before the router can update NTP time from internet. So after reboot the timestamps in the log are wrong... If you look closer at the system log, there is usually a gap/jump in time when it gets refreshed.
You are wrong. I wrote that the router did not crash, just the WiFi went down. I was still able to login via LAN, there has not been a reboot. So the timestamps should be correct and the logs could lead to useful information.
Interesting, did not know that.
However, since the logs seem to be correct, any ideas about them? Or should I create an issue on GitHub? Also ping @nbd since I saw you were working on similar log issues with different devices:
For now I will try to use the tip from @jeff to print out RAM usage to the terminal to see whether this might be the root.
Also I should note that until now I think I only experienced this problem after using the specific device with the mac address given on the IEEE 802.11: disconnected due to excessive missing ACKs error message (fc:a6:67:c6:9f:af). It is a FireTV Stick from Amazon.
Yeah, I misunderstood the details this time as the earlier part of the thread mentions reboots. But apparently wifi just doesn't accept connection from your device, but the router itself stays alive. And actually also the authentication driver (hostapd/wpad) stays alive, as there are further log messages.
As there is nothing visible on kernel log, there has not been an actual wifi driver "crash".
(A real wifi driver crash would show up visibly in the kernel log )
It is likely some kind of lockup either in the driver or in the hostapd authentication daemon. You might try identifying the culprit by trying to restart hostapd, and/or the whole wifi via "wifi up".
But the generic reason may well be the 32 MB RAM thing. It is really problematic. It may lead to e.g. some temporary buffer allocation failing, or something like like.
Since I did not activate the memory logging everytime, I did not have it when the crashes occurred.
Yesterday I tried a stress test meaning high streaming volumes on three connected Wifi devices and my PC to maybe provoke the crash. Unfortunately that did not work and also the free memory was rather stable and did never cause a crash.
Fortunately I enabled logging today and the Wifi just crashed now with normal use (no stress test).
root@LEDE:~# while printf "%s\t%s\n" "$(date)" "$(free | head -n2 | tail -n1)" ; do sleep 1 ; done
Wed Aug 21 20:39:24 CEST 2019 Mem: 27844 19312 8532 436 1320 3940
Wed Aug 21 20:39:25 CEST 2019 Mem: 27844 19308 8536 436 1320 3940
Wed Aug 21 20:39:26 CEST 2019 Mem: 27844 19436 8408 436 1320 3940
Wed Aug 21 20:39:27 CEST 2019 Mem: 27844 19396 8448 436 1320 3940
Wed Aug 21 20:39:28 CEST 2019 Mem: 27844 19380 8464 436 1320 3940
Wed Aug 21 20:39:29 CEST 2019 Mem: 27844 19500 8344 436 1320 3940
Wed Aug 21 20:39:30 CEST 2019 Mem: 27844 19492 8352 436 1320 3940
Wed Aug 21 20:39:31 CEST 2019 Mem: 27844 19204 8640 436 1320 3940
Wed Aug 21 20:39:32 CEST 2019 Mem: 27844 19304 8540 436 1320 3940
Wed Aug 21 20:39:33 CEST 2019 Mem: 27844 19424 8420 436 1320 3940
Wed Aug 21 20:39:34 CEST 2019 Mem: 27844 19560 8284 436 1320 3940
Wed Aug 21 20:39:35 CEST 2019 Mem: 27844 19480 8364 436 1320 3940
Wed Aug 21 20:39:36 CEST 2019 Mem: 27844 19244 8600 436 1320 3940
Wed Aug 21 20:39:37 CEST 2019 Mem: 27844 19408 8436 436 1320 3940
Wed Aug 21 20:39:38 CEST 2019 Mem: 27844 19540 8304 436 1320 3940
Wed Aug 21 20:39:39 CEST 2019 Mem: 27844 19596 8248 436 1320 3940
Wed Aug 21 20:39:40 CEST 2019 Mem: 27844 19132 8712 436 1320 3940
Wed Aug 21 20:39:41 CEST 2019 Mem: 27844 19752 8092 436 1320 3940
Wed Aug 21 20:39:43 CEST 2019 Mem: 27844 19280 8564 436 1320 3940
Wed Aug 21 20:39:44 CEST 2019 Mem: 27844 19372 8472 436 1320 3940
Wed Aug 21 20:39:45 CEST 2019 Mem: 27844 19532 8312 436 1320 3940
Wed Aug 21 20:39:46 CEST 2019 Mem: 27844 19628 8216 436 1320 3940
Wed Aug 21 20:39:47 CEST 2019 Mem: 27844 19696 8148 436 1320 3940
Wed Aug 21 20:39:48 CEST 2019 Mem: 27844 19432 8412 436 1320 3940
Wed Aug 21 20:39:49 CEST 2019 Mem: 27844 19364 8480 436 1320 3940
Wed Aug 21 20:39:50 CEST 2019 Mem: 27844 19392 8452 436 1320 3940
Wed Aug 21 20:39:51 CEST 2019 Mem: 27844 19468 8376 436 1320 3940
Wed Aug 21 20:39:52 CEST 2019 Mem: 27844 19624 8220 436 1320 3940
Wed Aug 21 20:39:53 CEST 2019 Mem: 27844 19564 8280 436 1320 3940
Wed Aug 21 20:39:54 CEST 2019 Mem: 27844 19652 8192 436 1320 3940
Wed Aug 21 20:39:55 CEST 2019 Mem: 27844 19340 8504 436 1320 3940
Wed Aug 21 20:39:56 CEST 2019 Mem: 27844 19396 8448 436 1320 3940
Wed Aug 21 20:39:57 CEST 2019 Mem: 27844 19488 8356 436 1320 3940
Wed Aug 21 20:39:58 CEST 2019 Mem: 27844 19624 8220 436 1320 3940
Wed Aug 21 20:39:59 CEST 2019 Mem: 27844 19692 8152 436 1320 3940
Wed Aug 21 20:40:00 CEST 2019 Mem: 27844 19684 8160 436 1320 3940
Wed Aug 21 20:40:01 CEST 2019 Mem: 27844 19680 8164 436 1320 3940
Wed Aug 21 20:40:02 CEST 2019 Mem: 27844 19660 8184 436 1320 3940
Wed Aug 21 20:40:03 CEST 2019 Mem: 27844 19676 8168 436 1320 3940
Wed Aug 21 20:40:04 CEST 2019 Mem: 27844 19692 8152 436 1320 3940
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Wed Aug 21 20:40:07 CEST 2019 Mem: 27844 19396 8448 436 1320 3940
Wed Aug 21 20:40:08 CEST 2019 Mem: 27844 19536 8308 436 1320 3940
Wed Aug 21 20:40:09 CEST 2019 Mem: 27844 19596 8248 436 1320 3940
Wed Aug 21 20:40:11 CEST 2019 Mem: 27844 19620 8224 436 1320 3940
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Wed Aug 21 20:40:13 CEST 2019 Mem: 27844 19664 8180 436 1320 3940
Wed Aug 21 20:40:14 CEST 2019 Mem: 27844 19696 8148 436 1320 3940
Wed Aug 21 20:40:15 CEST 2019 Mem: 27844 19792 8052 436 1320 3940
Wed Aug 21 20:40:16 CEST 2019 Mem: 27844 19848 7996 436 1320 3940
Wed Aug 21 20:40:17 CEST 2019 Mem: 27844 19792 8052 436 1320 3940
Wed Aug 21 20:40:18 CEST 2019 Mem: 27844 19664 8180 436 1320 3940
Wed Aug 21 20:40:19 CEST 2019 Mem: 27844 19724 8120 436 1320 3940
Wed Aug 21 20:40:20 CEST 2019 Mem: 27844 19696 8148 436 1320 3940
Wed Aug 21 20:40:21 CEST 2019 Mem: 27844 19756 8088 436 1320 3940
Wed Aug 21 20:40:22 CEST 2019 Mem: 27844 19680 8164 436 1320 3940
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Wed Aug 21 20:40:24 CEST 2019 Mem: 27844 19692 8152 436 1320 3940
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Wed Aug 21 20:40:30 CEST 2019 Mem: 27844 19620 8224 436 1320 3940
Wed Aug 21 20:40:31 CEST 2019 Mem: 27844 19752 8092 436 1320 3940
Wed Aug 21 20:40:32 CEST 2019 Mem: 27844 19748 8096 436 1320 3940
Wed Aug 21 20:40:33 CEST 2019 Mem: 27844 19720 8124 436 1320 3940
Wed Aug 21 20:40:34 CEST 2019 Mem: 27844 19740 8104 436 1320 3940
Wed Aug 21 20:40:35 CEST 2019 Mem: 27844 19276 8568 436 1320 3940
Wed Aug 21 20:40:36 CEST 2019 Mem: 27844 19468 8376 436 1320 3940
Wed Aug 21 20:40:37 CEST 2019 Mem: 27844 19568 8276 436 1320 3940
Wed Aug 21 20:40:38 CEST 2019 Mem: 27844 19652 8192 436 1320 3940
Wed Aug 21 20:40:39 CEST 2019 Mem: 27844 19752 8092 436 1320 3940
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Wed Aug 21 20:40:42 CEST 2019 Mem: 27844 19304 8540 436 1320 3940
Wed Aug 21 20:40:43 CEST 2019 Mem: 27844 19432 8412 436 1320 3940
Wed Aug 21 20:40:44 CEST 2019 Mem: 27844 19588 8256 436 1320 3940
Wed Aug 21 20:40:45 CEST 2019 Mem: 27844 19424 8420 436 1320 3940
Wed Aug 21 20:40:46 CEST 2019 Mem: 27844 19480 8364 436 1320 3940
Wed Aug 21 20:40:47 CEST 2019 Mem: 27844 19524 8320 436 1320 3940
Wed Aug 21 20:40:48 CEST 2019 Mem: 27844 19208 8636 436 1320 3940
Wed Aug 21 20:40:49 CEST 2019 Mem: 27844 19392 8452 436 1320 3940
Wed Aug 21 20:40:50 CEST 2019 Mem: 27844 19500 8344 436 1320 3940
Wed Aug 21 20:40:51 CEST 2019 Mem: 27844 19568 8276 436 1320 3940
Wed Aug 21 20:40:52 CEST 2019 Mem: 27844 19628 8216 436 1320 3940
Wed Aug 21 20:40:53 CEST 2019 Mem: 27844 19664 8180 436 1320 3940
Wed Aug 21 20:40:54 CEST 2019 Mem: 27844 19748 8096 436 1320 3940
Wed Aug 21 20:40:55 CEST 2019 Mem: 27844 19812 8032 436 1320 3940
Wed Aug 21 20:40:56 CEST 2019 Mem: 27844 19412 8432 436 1320 3940
Wed Aug 21 20:40:57 CEST 2019 Mem: 27844 19476 8368 436 1320 3940
Wed Aug 21 20:40:58 CEST 2019 Mem: 27844 19532 8312 436 1320 3940
Wed Aug 21 20:40:59 CEST 2019 Mem: 27844 19656 8188 436 1320 3940
Wed Aug 21 20:41:00 CEST 2019 Mem: 27844 19616 8228 436 1320 3940
Wed Aug 21 20:41:01 CEST 2019 Mem: 27844 19656 8188 436 1320 3940
Wed Aug 21 20:41:02 CEST 2019 Mem: 27844 19628 8216 436 1320 3940
Wed Aug 21 20:41:03 CEST 2019 Mem: 27844 19756 8088 436 1320 3940
Wed Aug 21 20:41:04 CEST 2019 Mem: 27844 19404 8440 436 1320 3940
Wed Aug 21 20:41:05 CEST 2019 Mem: 27844 19528 8316 436 1320 3940
Wed Aug 21 20:41:06 CEST 2019 Mem: 27844 19660 8184 436 1320 3940
Wed Aug 21 20:41:07 CEST 2019 Mem: 27844 19408 8436 436 1320 3940
Wed Aug 21 20:41:08 CEST 2019 Mem: 27844 19488 8356 436 1320 3940
Wed Aug 21 20:41:09 CEST 2019 Mem: 27844 19592 8252 436 1320 3940
Wed Aug 21 20:41:11 CEST 2019 Mem: 27844 19688 8156 436 1320 3940
Wed Aug 21 20:41:12 CEST 2019 Mem: 27844 19392 8452 436 1320 3940
Wed Aug 21 20:41:13 CEST 2019 Mem: 27844 19428 8416 436 1320 3940
Wed Aug 21 20:41:14 CEST 2019 Mem: 27844 19588 8256 436 1320 3940
Wed Aug 21 20:41:15 CEST 2019 Mem: 27844 19692 8152 436 1320 3940
Wed Aug 21 20:41:16 CEST 2019 Mem: 27844 19304 8540 436 1320 3940
Wed Aug 21 20:41:17 CEST 2019 Mem: 27844 19344 8500 436 1320 3940
Wed Aug 21 20:41:18 CEST 2019 Mem: 27844 19460 8384 436 1320 3940
Wed Aug 21 20:41:19 CEST 2019 Mem: 27844 19584 8260 436 1320 3940
Wed Aug 21 20:41:20 CEST 2019 Mem: 27844 19744 8100 436 1320 3940
Wed Aug 21 20:41:21 CEST 2019 Mem: 27844 19988 7856 436 1320 3940
Wed Aug 21 20:41:22 CEST 2019 Mem: 27844 19440 8404 436 1320 3940
Wed Aug 21 20:41:23 CEST 2019 Mem: 27844 19564 8280 436 1320 3940
Wed Aug 21 20:41:24 CEST 2019 Mem: 27844 19696 8148 436 1320 3940
Wed Aug 21 20:41:25 CEST 2019 Mem: 27844 19752 8092 436 1320 3940
Wed Aug 21 20:41:26 CEST 2019 Mem: 27844 19596 8248 436 1320 3940
Wed Aug 21 20:41:27 CEST 2019 Mem: 27844 19592 8252 436 1320 3940
Wed Aug 21 20:41:28 CEST 2019 Mem: 27844 19576 8268 436 1320 3940
Wed Aug 21 20:41:29 CEST 2019 Mem: 27844 19568 8276 436 1320 3940
Wed Aug 21 20:41:30 CEST 2019 Mem: 27844 19628 8216 436 1320 3940
Wed Aug 21 20:41:31 CEST 2019 Mem: 27844 20056 7788 436 1320 3940
Wed Aug 21 20:41:32 CEST 2019 Mem: 27844 19748 8096 436 1320 3940
Wed Aug 21 20:41:34 CEST 2019 Mem: 27844 19488 8356 436 1320 3940
Wed Aug 21 20:41:35 CEST 2019 Mem: 27844 19620 8224 436 1320 3940
Wed Aug 21 20:41:36 CEST 2019 Mem: 27844 19632 8212 436 1320 3940
Wed Aug 21 20:41:37 CEST 2019 Mem: 27844 19712 8132 436 1320 3940
Wed Aug 21 20:41:38 CEST 2019 Mem: 27844 19732 8112 436 1320 3940
Wed Aug 21 20:41:39 CEST 2019 Mem: 27844 19704 8140 436 1320 3940
Wed Aug 21 20:41:40 CEST 2019 Mem: 27844 19728 8116 436 1320 3940
Wed Aug 21 20:41:41 CEST 2019 Mem: 27844 19824 8020 436 1320 3940
Wed Aug 21 20:41:42 CEST 2019 Mem: 27844 19732 8112 436 1320 3940
Wed Aug 21 20:41:43 CEST 2019 Mem: 27844 19760 8084 436 1320 3940
Wed Aug 21 20:41:44 CEST 2019 Mem: 27844 19552 8292 436 1320 3940
Wed Aug 21 20:41:45 CEST 2019 Mem: 27844 19668 8176 436 1320 3940
Wed Aug 21 20:41:46 CEST 2019 Mem: 27844 19704 8140 436 1320 3940
Wed Aug 21 20:41:47 CEST 2019 Mem: 27844 19732 8112 436 1320 3940
Wed Aug 21 20:41:48 CEST 2019 Mem: 27844 19636 8208 436 1320 3940
Wed Aug 21 20:41:49 CEST 2019 Mem: 27844 19600 8244 436 1320 3940
Wed Aug 21 20:41:50 CEST 2019 Mem: 27844 19396 8448 436 1320 3940
Wed Aug 21 20:41:51 CEST 2019 Mem: 27844 19588 8256 436 1320 3940
Wed Aug 21 20:41:52 CEST 2019 Mem: 27844 19660 8184 436 1320 3940
Wed Aug 21 20:41:53 CEST 2019 Mem: 27844 19440 8404 436 1320 3940
Wed Aug 21 20:41:54 CEST 2019 Mem: 27844 19676 8168 436 1320 3940
Wed Aug 21 20:41:55 CEST 2019 Mem: 27844 19784 8060 436 1320 3940
Wed Aug 21 20:41:56 CEST 2019 Mem: 27844 19788 8056 436 1320 3940
Wed Aug 21 20:41:57 CEST 2019 Mem: 27844 19540 8304 436 1320 3940
Wed Aug 21 20:41:58 CEST 2019 Mem: 27844 19656 8188 436 1320 3940
Wed Aug 21 20:41:59 CEST 2019 Mem: 27844 19748 8096 436 1320 3940
Wed Aug 21 20:42:01 CEST 2019 Mem: 27844 20276 7568 436 1320 3940
Wed Aug 21 20:42:02 CEST 2019 Mem: 27844 19856 7988 436 1320 3940
Wed Aug 21 20:42:03 CEST 2019 Mem: 27844 19896 7948 436 1320 3940
Wed Aug 21 20:42:04 CEST 2019 Mem: 27844 19888 7956 436 1320 3940
Wed Aug 21 20:42:05 CEST 2019 Mem: 27844 19724 8120 436 1320 3940
Wed Aug 21 20:42:06 CEST 2019 Mem: 27844 19812 8032 436 1320 3940
Wed Aug 21 20:42:07 CEST 2019 Mem: 27844 19924 7920 436 1320 3940
Wed Aug 21 20:42:08 CEST 2019 Mem: 27844 19664 8180 436 1320 3940
Wed Aug 21 20:42:09 CEST 2019 Mem: 27844 19760 8084 436 1320 3940
Wed Aug 21 20:42:10 CEST 2019 Mem: 27844 19856 7988 436 1320 3940
Wed Aug 21 20:42:11 CEST 2019 Mem: 27844 19952 7892 436 1320 3940
Wed Aug 21 20:42:12 CEST 2019 Mem: 27844 19952 7892 436 1320 3940
Wed Aug 21 20:42:13 CEST 2019 Mem: 27844 19952 7892 436 1320 3940
Wed Aug 21 20:42:14 CEST 2019 Mem: 27844 20012 7832 436 1320 3940
Wed Aug 21 20:42:15 CEST 2019 Mem: 27844 19900 7944 436 1320 3940
Wed Aug 21 20:42:16 CEST 2019 Mem: 27844 20016 7828 436 1320 3940
Wed Aug 21 20:42:17 CEST 2019 Mem: 27844 19916 7928 436 1320 3940
Wed Aug 21 20:42:18 CEST 2019 Mem: 27844 19872 7972 436 1320 3940
Wed Aug 21 20:42:19 CEST 2019 Mem: 27844 20012 7832 436 1320 3940
Wed Aug 21 20:42:20 CEST 2019 Mem: 27844 19572 8272 436 1320 3940
Wed Aug 21 20:42:21 CEST 2019 Mem: 27844 19724 8120 436 1320 3940
Wed Aug 21 20:42:22 CEST 2019 Mem: 27844 19920 7924 436 1320 3940
Wed Aug 21 20:42:23 CEST 2019 Mem: 27844 20016 7828 436 1320 3940
Wed Aug 21 20:42:24 CEST 2019 Mem: 27844 19652 8192 436 1320 3940
Wed Aug 21 20:42:25 CEST 2019 Mem: 27844 19748 8096 436 1320 3940
Wed Aug 21 20:42:26 CEST 2019 Mem: 27844 19856 7988 436 1320 3940
Wed Aug 21 20:42:28 CEST 2019 Mem: 27844 19856 7988 436 1320 3940
Wed Aug 21 20:42:29 CEST 2019 Mem: 27844 19856 7988 436 1320 3940
Wed Aug 21 20:42:30 CEST 2019 Mem: 27844 19936 7908 436 1320 3940
Wed Aug 21 20:42:31 CEST 2019 Mem: 27844 19980 7864 436 1320 3940
Wed Aug 21 20:42:32 CEST 2019 Mem: 27844 19564 8280 436 1320 3940
Wed Aug 21 20:42:33 CEST 2019 Mem: 27844 19732 8112 436 1320 3940
Wed Aug 21 20:42:34 CEST 2019 Mem: 27844 19788 8056 436 1320 3940
Wed Aug 21 20:42:35 CEST 2019 Mem: 27844 19400 8444 436 1320 3940
Wed Aug 21 20:42:36 CEST 2019 Mem: 27844 19520 8324 436 1320 3940
Wed Aug 21 20:42:37 CEST 2019 Mem: 27844 19588 8256 436 1320 3940
Wed Aug 21 20:42:38 CEST 2019 Mem: 27844 19648 8196 436 1320 3940
Wed Aug 21 20:42:39 CEST 2019 Mem: 27844 19776 8068 436 1320 3940
Wed Aug 21 20:42:40 CEST 2019 Mem: 27844 19844 8000 436 1320 3940
Wed Aug 21 20:42:41 CEST 2019 Mem: 27844 19844 8000 436 1320 3940
Wed Aug 21 20:42:42 CEST 2019 Mem: 27844 19784 8060 436 1320 3940
Wed Aug 21 20:42:43 CEST 2019 Mem: 27844 19772 8072 436 1320 3940
Wed Aug 21 20:42:44 CEST 2019 Mem: 27844 19564 8280 436 1320 3940
Wed Aug 21 20:42:45 CEST 2019 Mem: 27844 19656 8188 436 1320 3940
Wed Aug 21 20:42:46 CEST 2019 Mem: 27844 19712 8132 436 1320 3940
Wed Aug 21 20:42:47 CEST 2019 Mem: 27844 19724 8120 436 1320 3940
Wed Aug 21 20:42:48 CEST 2019 Mem: 27844 19496 8348 436 1320 3940
Wed Aug 21 20:42:49 CEST 2019 Mem: 27844 19576 8268 436 1320 3940
Wed Aug 21 20:42:50 CEST 2019 Mem: 27844 19724 8120 436 1320 3940
Wed Aug 21 20:42:51 CEST 2019 Mem: 27844 19660 8184 436 1320 3940
Wed Aug 21 20:42:52 CEST 2019 Mem: 27844 19720 8124 436 1320 3940
Wed Aug 21 20:42:53 CEST 2019 Mem: 27844 19692 8152 436 1320 3940
Wed Aug 21 20:42:54 CEST 2019 Mem: 27844 19720 8124 436 1320 3940
Wed Aug 21 20:42:55 CEST 2019 Mem: 27844 19744 8100 436 1320 3940
Wed Aug 21 20:42:57 CEST 2019 Mem: 27844 19436 8408 436 1320 3940
Wed Aug 21 20:42:58 CEST 2019 Mem: 27844 19532 8312 436 1320 3940
Wed Aug 21 20:42:59 CEST 2019 Mem: 27844 19624 8220 436 1320 3940
Wed Aug 21 20:43:00 CEST 2019 Mem: 27844 19700 8144 436 1320 3940
Wed Aug 21 20:43:01 CEST 2019 Mem: 27844 19592 8252 436 1320 3940
Wed Aug 21 20:43:02 CEST 2019 Mem: 27844 19628 8216 436 1320 3940
Wed Aug 21 20:43:03 CEST 2019 Mem: 27844 19784 8060 436 1320 3940
Wed Aug 21 20:43:04 CEST 2019 Mem: 27844 19780 8064 436 1320 3940
Wed Aug 21 20:43:05 CEST 2019 Mem: 27844 19680 8164 436 1320 3940
Wed Aug 21 20:43:06 CEST 2019 Mem: 27844 19452 8392 436 1320 3940
Wed Aug 21 20:43:07 CEST 2019 Mem: 27844 19660 8184 436 1320 3940
Wed Aug 21 20:43:08 CEST 2019 Mem: 27844 19752 8092 436 1320 3940
Wed Aug 21 20:43:09 CEST 2019 Mem: 27844 19796 8048 436 1320 3940
Wed Aug 21 20:43:10 CEST 2019 Mem: 27844 19588 8256 436 1320 3940
Wed Aug 21 20:43:11 CEST 2019 Mem: 27844 19664 8180 436 1320 3940
Wed Aug 21 20:43:12 CEST 2019 Mem: 27844 19788 8056 436 1320 3940
Wed Aug 21 20:43:13 CEST 2019 Mem: 27844 19916 7928 436 1320 3940
Wed Aug 21 20:43:14 CEST 2019 Mem: 27844 19912 7932 436 1320 3940
Wed Aug 21 20:43:15 CEST 2019 Mem: 27844 19596 8248 436 1320 3940
Wed Aug 21 20:43:16 CEST 2019 Mem: 27844 19608 8236 436 1320 3940
Wed Aug 21 20:43:17 CEST 2019 Mem: 27844 19764 8080 436 1320 3940
Wed Aug 21 20:43:18 CEST 2019 Mem: 27844 19860 7984 436 1320 3940
Wed Aug 21 20:43:19 CEST 2019 Mem: 27844 19752 8092 436 1320 3940
Wed Aug 21 20:43:20 CEST 2019 Mem: 27844 19752 8092 436 1320 3940
Wed Aug 21 20:43:21 CEST 2019 Mem: 27844 19760 8084 436 1320 3940
Wed Aug 21 20:43:22 CEST 2019 Mem: 27844 19868 7976 436 1320 3940
Wed Aug 21 20:43:23 CEST 2019 Mem: 27844 19928 7916 436 1320 3940
Wed Aug 21 20:43:25 CEST 2019 Mem: 27844 20024 7820 436 1320 3940
Wed Aug 21 20:43:26 CEST 2019 Mem: 27844 19992 7852 436 1320 3940
Wed Aug 21 20:43:27 CEST 2019 Mem: 27844 19864 7980 436 1320 3940
Wed Aug 21 20:43:28 CEST 2019 Mem: 27844 19724 8120 436 1320 3940
Wed Aug 21 20:43:29 CEST 2019 Mem: 27844 19760 8084 436 1320 3940
Wed Aug 21 20:43:30 CEST 2019 Mem: 27844 19852 7992 436 1320 3940
Wed Aug 21 20:43:31 CEST 2019 Mem: 27844 19952 7892 436 1320 3940
Wed Aug 21 20:43:32 CEST 2019 Mem: 27844 20040 7804 436 1320 3940
Wed Aug 21 20:43:33 CEST 2019 Mem: 27844 19976 7868 436 1320 3940
Wed Aug 21 20:43:34 CEST 2019 Mem: 27844 19680 8164 436 1320 3940
Wed Aug 21 20:43:35 CEST 2019 Mem: 27844 19736 8108 436 1320 3940
Wed Aug 21 20:43:36 CEST 2019 Mem: 27844 19888 7956 436 1320 3940
Wed Aug 21 20:43:37 CEST 2019 Mem: 27844 20016 7828 436 1320 3940
Wed Aug 21 20:43:38 CEST 2019 Mem: 27844 19724 8120 436 1320 3940
Wed Aug 21 20:43:39 CEST 2019 Mem: 27844 19948 7896 436 1320 3940
Wed Aug 21 20:43:40 CEST 2019 Mem: 27844 20080 7764 436 1320 3940
Wed Aug 21 20:43:41 CEST 2019 Mem: 27844 20012 7832 436 1320 3940
Wed Aug 21 20:43:42 CEST 2019 Mem: 27844 20016 7828 436 1320 3940
Wed Aug 21 20:43:43 CEST 2019 Mem: 27844 20020 7824 436 1320 3940
Wed Aug 21 20:43:44 CEST 2019 Mem: 27844 20016 7828 436 1320 3940
Wed Aug 21 20:43:45 CEST 2019 Mem: 27844 20040 7804 436 1320 3940
Wed Aug 21 20:43:46 CEST 2019 Mem: 27844 20012 7832 436 1320 3940
Wed Aug 21 20:43:47 CEST 2019 Mem: 27844 20008 7836 436 1320 3940
Wed Aug 21 20:43:48 CEST 2019 Mem: 27844 19928 7916 436 1320 3940
Wed Aug 21 20:43:49 CEST 2019 Mem: 27844 19916 7928 436 1320 3940
Wed Aug 21 20:43:50 CEST 2019 Mem: 27844 20008 7836 436 1320 3940
^C
System log (does not show anything special):
Wed Aug 21 19:28:03 2019 daemon.info dnsmasq-dhcp[1490]: DHCPACK(br-lan) 192.168.1.112 fc:a6:67:c6:9f:af fire-tv-stick
Wed Aug 21 19:28:05 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 19:34:32 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 19:39:02 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 19:46:00 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 19:52:56 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 19:59:38 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 20:05:53 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 20:09:02 2019 daemon.info dnsmasq-dhcp[1490]: DHCPREQUEST(br-lan) 192.168.1.168 48:d6:d5:6a:85:66
Wed Aug 21 20:09:02 2019 daemon.info dnsmasq-dhcp[1490]: DHCPACK(br-lan) 192.168.1.168 48:d6:d5:6a:85:66 google-home
Wed Aug 21 20:09:17 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 20:13:16 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 20:22:45 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 20:26:39 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 20:33:14 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 20:33:26 2019 daemon.info dnsmasq-dhcp[1490]: DHCPREQUEST(br-lan) 192.168.1.110 68:54:fd:e6:c3:c8
Wed Aug 21 20:33:26 2019 daemon.info dnsmasq-dhcp[1490]: DHCPACK(br-lan) 192.168.1.110 68:54:fd:e6:c3:c8 echo-dot
Wed Aug 21 20:42:48 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 20:46:43 2019 daemon.err uhttpd[904]: luci: accepted login on / for root from fdd5:24c4:abb4::98d3:c572:7f69:31c
So as you can see the memory did not seem to drop before the crash. Thus it is probably not the reason for the crash. I will also try the suggestions of @hnyman just now.
It is. You cant log/see the moment of crash. Ive tried to remote log/USB log. Just don`t bother.
Get rid of LUCI and PPP (build yourself)
Get used to CLI
Unfortunately I did not know how to restart hostapd and did not find any helpful information via Google. So I just did wifi up (at around 21:15 where many events are logged) and that worked.
System log:
Wed Aug 21 20:46:43 2019 daemon.err uhttpd[904]: luci: accepted login on / for root from fdd5:24c4:abb4::98d3:c572:7f69:31c
Wed Aug 21 20:49:21 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 20:49:37 2019 daemon.notice hostapd: wlan0: AP-STA-DISCONNECTED 1c:12:b0:e0:93:0d
Wed Aug 21 20:49:37 2019 daemon.info hostapd: wlan0: STA 1c:12:b0:e0:93:0d IEEE 802.11: disassociated due to inactivity
Wed Aug 21 20:49:38 2019 daemon.notice hostapd: wlan0: AP-STA-DISCONNECTED 34:ea:34:f4:3c:42
Wed Aug 21 20:49:38 2019 daemon.info hostapd: wlan0: STA 34:ea:34:f4:3c:42 IEEE 802.11: disassociated due to inactivity
Wed Aug 21 20:49:38 2019 daemon.info hostapd: wlan0: STA 1c:12:b0:e0:93:0d IEEE 802.11: deauthenticated due to inactivity (timer DEAUTH/REMOVE)
Wed Aug 21 20:49:39 2019 daemon.info hostapd: wlan0: STA 34:ea:34:f4:3c:42 IEEE 802.11: deauthenticated due to inactivity (timer DEAUTH/REMOVE)
Wed Aug 21 20:49:51 2019 daemon.notice hostapd: wlan0: AP-STA-DISCONNECTED 3c:bd:3e:57:ee:c1
Wed Aug 21 20:49:51 2019 daemon.info hostapd: wlan0: STA 3c:bd:3e:57:ee:c1 IEEE 802.11: disassociated due to inactivity
Wed Aug 21 20:49:52 2019 daemon.info hostapd: wlan0: STA 3c:bd:3e:57:ee:c1 IEEE 802.11: deauthenticated due to inactivity (timer DEAUTH/REMOVE)
Wed Aug 21 20:49:52 2019 daemon.notice hostapd: wlan0: AP-STA-DISCONNECTED 68:54:fd:e6:c3:c8
Wed Aug 21 20:49:52 2019 daemon.info hostapd: wlan0: STA 68:54:fd:e6:c3:c8 IEEE 802.11: disassociated due to inactivity
Wed Aug 21 20:49:53 2019 daemon.info hostapd: wlan0: STA 68:54:fd:e6:c3:c8 IEEE 802.11: deauthenticated due to inactivity (timer DEAUTH/REMOVE)
Wed Aug 21 20:49:54 2019 daemon.notice hostapd: wlan0: AP-STA-DISCONNECTED 7c:49:eb:15:66:bd
Wed Aug 21 20:49:54 2019 daemon.info hostapd: wlan0: STA 7c:49:eb:15:66:bd IEEE 802.11: disassociated due to inactivity
Wed Aug 21 20:49:54 2019 daemon.notice hostapd: wlan0: AP-STA-DISCONNECTED fc:a6:67:c6:9f:af
Wed Aug 21 20:49:54 2019 daemon.info hostapd: wlan0: STA fc:a6:67:c6:9f:af IEEE 802.11: disassociated due to inactivity
Wed Aug 21 20:49:55 2019 daemon.info hostapd: wlan0: STA 7c:49:eb:15:66:bd IEEE 802.11: deauthenticated due to inactivity (timer DEAUTH/REMOVE)
Wed Aug 21 20:49:55 2019 daemon.notice hostapd: wlan0: AP-STA-DISCONNECTED 48:d6:d5:6a:85:66
Wed Aug 21 20:49:55 2019 daemon.info hostapd: wlan0: STA 48:d6:d5:6a:85:66 IEEE 802.11: disassociated due to inactivity
Wed Aug 21 20:49:55 2019 daemon.notice hostapd: wlan0: AP-STA-DISCONNECTED 40:31:3c:a4:6f:cb
Wed Aug 21 20:49:55 2019 daemon.info hostapd: wlan0: STA 40:31:3c:a4:6f:cb IEEE 802.11: disassociated due to inactivity
Wed Aug 21 20:49:55 2019 daemon.info hostapd: wlan0: STA fc:a6:67:c6:9f:af IEEE 802.11: deauthenticated due to inactivity (timer DEAUTH/REMOVE)
Wed Aug 21 20:49:56 2019 daemon.info hostapd: wlan0: STA 48:d6:d5:6a:85:66 IEEE 802.11: deauthenticated due to inactivity (timer DEAUTH/REMOVE)
Wed Aug 21 20:49:56 2019 daemon.info hostapd: wlan0: STA 40:31:3c:a4:6f:cb IEEE 802.11: deauthenticated due to inactivity (timer DEAUTH/REMOVE)
Wed Aug 21 20:49:58 2019 daemon.notice hostapd: wlan0: AP-STA-DISCONNECTED f0:d7:aa:00:7e:9d
Wed Aug 21 20:49:58 2019 daemon.info hostapd: wlan0: STA f0:d7:aa:00:7e:9d IEEE 802.11: disassociated due to inactivity
Wed Aug 21 20:49:59 2019 daemon.info hostapd: wlan0: STA f0:d7:aa:00:7e:9d IEEE 802.11: deauthenticated due to inactivity (timer DEAUTH/REMOVE)
Wed Aug 21 20:58:09 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 21:05:49 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 21:13:44 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 21:15:45 2019 daemon.notice hostapd: wlan0: interface state ENABLED->DISABLED
Wed Aug 21 21:15:45 2019 daemon.notice hostapd: wlan0: AP-DISABLED
Wed Aug 21 21:15:45 2019 daemon.notice hostapd: wlan0: CTRL-EVENT-TERMINATING
Wed Aug 21 21:15:45 2019 daemon.notice hostapd: nl80211: deinit ifname=wlan0 disabled_11b_rates=0
Wed Aug 21 21:15:45 2019 kern.info kernel: [250379.414460] device wlan0 left promiscuous mode
Wed Aug 21 21:15:45 2019 kern.info kernel: [250379.419447] br-lan: port 2(wlan0) entered disabled state
Wed Aug 21 21:15:45 2019 daemon.notice netifd: Network device 'wlan0' link is down
Wed Aug 21 21:15:46 2019 user.notice mac80211: Failed command: iw phy phy0 set antenna all all
Wed Aug 21 21:15:46 2019 daemon.err hostapd: Configuration file: /var/run/hostapd-phy0.conf
Wed Aug 21 21:15:46 2019 kern.info kernel: [250381.315257] IPv6: ADDRCONF(NETDEV_UP): wlan0: link is not ready
Wed Aug 21 21:15:47 2019 kern.info kernel: [250381.381199] br-lan: port 2(wlan0) entered blocking state
Wed Aug 21 21:15:47 2019 kern.info kernel: [250381.386800] br-lan: port 2(wlan0) entered disabled state
Wed Aug 21 21:15:47 2019 kern.info kernel: [250381.392979] device wlan0 entered promiscuous mode
Wed Aug 21 21:15:47 2019 daemon.notice hostapd: wlan0: interface state UNINITIALIZED->COUNTRY_UPDATE
Wed Aug 21 21:15:47 2019 daemon.err hostapd: Using interface wlan0 with hwaddr e8:94:f6:2a:c5:56 and ssid "clel"
Wed Aug 21 21:15:47 2019 daemon.notice hostapd: wlan0: interface state COUNTRY_UPDATE->ENABLED
Wed Aug 21 21:15:47 2019 daemon.notice hostapd: wlan0: AP-ENABLED
Wed Aug 21 21:15:47 2019 kern.info kernel: [250382.067816] IPv6: ADDRCONF(NETDEV_CHANGE): wlan0: link becomes ready
Wed Aug 21 21:15:47 2019 kern.info kernel: [250382.074854] br-lan: port 2(wlan0) entered blocking state
Wed Aug 21 21:15:47 2019 kern.info kernel: [250382.080514] br-lan: port 2(wlan0) entered forwarding state
Wed Aug 21 21:15:47 2019 daemon.notice netifd: Network device 'wlan0' link is up
Wed Aug 21 21:15:48 2019 daemon.info hostapd: wlan0: STA 7c:49:eb:15:66:bd IEEE 802.11: authenticated
Wed Aug 21 21:15:48 2019 daemon.info hostapd: wlan0: STA 7c:49:eb:15:66:bd IEEE 802.11: associated (aid 1)
Wed Aug 21 21:15:48 2019 daemon.notice hostapd: wlan0: AP-STA-CONNECTED 7c:49:eb:15:66:bd
Wed Aug 21 21:15:48 2019 daemon.info hostapd: wlan0: STA 7c:49:eb:15:66:bd WPA: pairwise key handshake completed (RSN)
Wed Aug 21 21:15:48 2019 daemon.info hostapd: wlan0: STA 68:54:fd:e6:c3:c8 IEEE 802.11: authenticated
Wed Aug 21 21:15:48 2019 daemon.info hostapd: wlan0: STA 68:54:fd:e6:c3:c8 IEEE 802.11: associated (aid 2)
Wed Aug 21 21:15:48 2019 daemon.notice hostapd: wlan0: AP-STA-CONNECTED 68:54:fd:e6:c3:c8
Wed Aug 21 21:15:48 2019 daemon.info hostapd: wlan0: STA 68:54:fd:e6:c3:c8 WPA: pairwise key handshake completed (RSN)
Wed Aug 21 21:15:49 2019 daemon.info dnsmasq-dhcp[1490]: DHCPREQUEST(br-lan) 192.168.1.110 68:54:fd:e6:c3:c8
Wed Aug 21 21:15:49 2019 daemon.info dnsmasq-dhcp[1490]: DHCPACK(br-lan) 192.168.1.110 68:54:fd:e6:c3:c8 echo-dot
Wed Aug 21 21:15:49 2019 daemon.info hostapd: wlan0: STA 40:31:3c:a4:6f:cb IEEE 802.11: authenticated
Wed Aug 21 21:15:49 2019 daemon.info hostapd: wlan0: STA 40:31:3c:a4:6f:cb IEEE 802.11: associated (aid 3)
Wed Aug 21 21:15:49 2019 daemon.info hostapd: wlan0: STA 34:ea:34:f4:3c:42 IEEE 802.11: authenticated
Wed Aug 21 21:15:49 2019 daemon.info hostapd: wlan0: STA 34:ea:34:f4:3c:42 IEEE 802.11: associated (aid 4)
Wed Aug 21 21:15:49 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Wed Aug 21 21:15:50 2019 daemon.info dnsmasq-dhcp[1490]: DHCPDISCOVER(br-lan) 7c:49:eb:15:66:bd
Wed Aug 21 21:15:50 2019 daemon.info dnsmasq-dhcp[1490]: DHCPOFFER(br-lan) 192.168.1.236 7c:49:eb:15:66:bd
Wed Aug 21 21:15:50 2019 daemon.info dnsmasq-dhcp[1490]: DHCPREQUEST(br-lan) 192.168.1.236 7c:49:eb:15:66:bd
Wed Aug 21 21:15:50 2019 daemon.info dnsmasq-dhcp[1490]: DHCPACK(br-lan) 192.168.1.236 7c:49:eb:15:66:bd yeelight-color-2
Wed Aug 21 21:15:50 2019 daemon.notice hostapd: wlan0: AP-STA-CONNECTED 34:ea:34:f4:3c:42
Wed Aug 21 21:15:50 2019 daemon.info hostapd: wlan0: STA 34:ea:34:f4:3c:42 WPA: pairwise key handshake completed (RSN)
Wed Aug 21 21:15:50 2019 daemon.info dnsmasq-dhcp[1490]: DHCPDISCOVER(br-lan) 34:ea:34:f4:3c:42
Wed Aug 21 21:15:50 2019 daemon.info dnsmasq-dhcp[1490]: DHCPOFFER(br-lan) 192.168.1.107 34:ea:34:f4:3c:42
Wed Aug 21 21:15:50 2019 daemon.info dnsmasq-dhcp[1490]: DHCPREQUEST(br-lan) 192.168.1.107 34:ea:34:f4:3c:42
Wed Aug 21 21:15:50 2019 daemon.info dnsmasq-dhcp[1490]: DHCPACK(br-lan) 192.168.1.107 34:ea:34:f4:3c:42 broadlink-rm-pro
Wed Aug 21 21:15:52 2019 daemon.info hostapd: wlan0: STA 40:31:3c:a4:6f:cb IEEE 802.11: authenticated
Wed Aug 21 21:15:52 2019 daemon.info hostapd: wlan0: STA 40:31:3c:a4:6f:cb IEEE 802.11: associated (aid 3)
Wed Aug 21 21:15:52 2019 daemon.notice hostapd: wlan0: AP-STA-CONNECTED 40:31:3c:a4:6f:cb
Wed Aug 21 21:15:52 2019 daemon.info hostapd: wlan0: STA 40:31:3c:a4:6f:cb WPA: pairwise key handshake completed (RSN)
Wed Aug 21 21:15:52 2019 daemon.info hostapd: wlan0: STA 1c:12:b0:e0:93:0d IEEE 802.11: authenticated
Wed Aug 21 21:15:52 2019 daemon.info hostapd: wlan0: STA 1c:12:b0:e0:93:0d IEEE 802.11: associated (aid 5)
Wed Aug 21 21:15:52 2019 daemon.notice hostapd: wlan0: AP-STA-CONNECTED 1c:12:b0:e0:93:0d
Wed Aug 21 21:15:52 2019 daemon.info hostapd: wlan0: STA 1c:12:b0:e0:93:0d WPA: pairwise key handshake completed (RSN)
Wed Aug 21 21:15:52 2019 daemon.info hostapd: wlan0: STA 48:d6:d5:6a:85:66 IEEE 802.11: authenticated
Wed Aug 21 21:15:52 2019 daemon.info hostapd: wlan0: STA 48:d6:d5:6a:85:66 IEEE 802.11: associated (aid 6)
Wed Aug 21 21:15:52 2019 daemon.notice hostapd: wlan0: AP-STA-CONNECTED 48:d6:d5:6a:85:66
Wed Aug 21 21:15:52 2019 daemon.info hostapd: wlan0: STA 48:d6:d5:6a:85:66 WPA: pairwise key handshake completed (RSN)
Wed Aug 21 21:15:52 2019 daemon.info dnsmasq-dhcp[1490]: DHCPREQUEST(br-lan) 192.168.1.168 48:d6:d5:6a:85:66
Wed Aug 21 21:15:52 2019 daemon.info dnsmasq-dhcp[1490]: DHCPACK(br-lan) 192.168.1.168 48:d6:d5:6a:85:66 google-home
Wed Aug 21 21:15:53 2019 daemon.info dnsmasq-dhcp[1490]: DHCPREQUEST(br-lan) 192.168.1.186 1c:12:b0:e0:93:0d
Wed Aug 21 21:15:53 2019 daemon.info dnsmasq-dhcp[1490]: DHCPACK(br-lan) 192.168.1.186 1c:12:b0:e0:93:0d fire-tablet
Wed Aug 21 21:15:53 2019 daemon.info odhcpd[848]: Using a RA lifetime of 0 seconds on br-lan
Well, I had around 8 MB of free RAM during the crash (1 second around it). So you are saying something just took 8 MB in this time? Might be true, I am not an expert. For now that does not look plausible.
I did not access LUCI during that time, also as I said I could not reproduce the crash with a stress test.
BTW: Do you have the same device? Do/did you experience the same problems? Did you create a forum post about this, so I can read more about it? Seems that you invested some time into researching your problem.
If you nearly run out of RAM the "out of memory killer" will start killing processes including important ones like hostapd and even more important ones like dropbear.
So you say it is possible that I ran out of RAM according to the log? Also, is there a way to check, whether something has been killed, like enabling more detailed logging, to see whether the "out of memory killer" did kill a process? For now there is no real proof that this happened and I want to be sure. Also, is there an easy way to reach out of RAM state with some stress test?
Sad that you did not give more details on what you experienced. Do you have the same device, is there a forum post describing the problem you had? Just posting the link to a site how to build custom images does not help.
I'm particularly interested in your: channel selection, power, distance optimization and group key interval; but show all of your /etc/config/wireless - blanking out sensitive things like the key, etc.
I stepped into this hw situation, however I barely noticed downtimes. I will keep an eye open and report back. Btw, <<<OpenWrt 18.06.4 r7808-ef686b7292 / LuCI openwrt-18.06 branch (git-19.170.32094-4d6d8bc)>>> on device <<<TP-Link TL-WR841N/ND v9>>>
I've got exactly same weird problem with TL-WR841N v8 running OpenWrt 15.05.1. The router is set to dumb AP mode, with minimum daemons running and maybe two clients connected over WLAN. There are two VLANS (bridge over WLAN and some switch port). In normal day, WiFi stays stable, but it stop accepting new connecting just after few hours of doing Timemachine backups. Timemachine server is running on cable connected Raspberry Pi (not on a router). I will try to stop luci too and also thinking about upgrading it's RAM. I still prefer to upgrade flash and RAM over dumping it to the trash and buy new router (mostly because I like to hack things and environmental concerns). The flash chip is on a way. After upgrade flash to 16mb I will upgrade OpenWrt to 18.06.x. But RAM upgrade is more tricky, as I don't have heat gun yet.
The question here, if there is problem with VLAN routing, because before switching to VLANS, I used default bridge mode (with much more daemons running) and at least one Timemachine backup was succesful. With VLANs, router WIFI stop acting weird after few hours, way before Timemachine backup can finish. But also remember similar router freeze before, with streaming cca 8h videos from minidlna (default bridge mode, no VLANs, but believe that time the LAN port to RasPi was dead instead and WiFi was still working).
I know its a bit later from the last post on this issue, but I have found that the wifi dies on the wr841n v9 (qca9533 v1) when a PS4 OG is in standby mode. This happens with even stock firmware. If you turn it completely off, the router will go for days and no wifi issue.