Release [Fork] Asuswrt-Merlin 374 LTS release 49E4

[frazor77]

TBH I don't think another PSU would have helped. The error messages are completely consistent between you and the other AC66U owners with this problem.

Doh, of course, that's a very valid point. In which case I'm on standby if there's any additional data/testing/debugging that I can assist with to help diagnose further.

 

[Nite01]

My router just rebooted on its own (RT-AC66U with this firmware version)
This is the log : https://pastebin.com/XnkdWHYi

I installed this firmware coming from the stock latest version. I did a factory default reset following the firmware flash (I did it with the asus utility) and used the Format JFFS partition at next boot function (after installing the firmware).
It worked without any problem for a couple of weeks until now.

 

[ColinTaylor]

My router just rebooted on its own (RT-AC66U with this firmware version)
This is the log : https://pastebin.com/JsxEZ2VJ

Unfortunately your log file doesn't go back far enough to be useful. But it does sound the same as the problems reported above.

 

[Nite01]

Unfortunately your log file doesn't go back far enough to be useful. But it does sound the same as the problems reported above.

Ok, I just read the last few pages, it seems a common problem for RT-AC66U.
Is there a known firmware version that didnt have this issue ? Or maybe I should flash again the stock firmware (should I do it with the asus utility in case ?) (I REALLY need this router to be stable)

 

[ColinTaylor]

Ok, I just read the last few pages, it seems a common problem for RT-AC66U.
Is there a known firmware version that didnt have this issue ? Or maybe I should flash again the stock firmware (should I do it with the asus utility in case ?) (I REALLY need this router to be stable)

@tsanga said in post #109 "The last stable release for me was 46Ex".

@frazor77 said in post #96 that he's been having problems since he installed 48E2.

So you could try 46E8, 46E9 or 47EB. Or try stock firmware (it's probably OK to flash that straight from the GUI).

 

[Nite01]

@tsanga said in post #109 "The last stable release for me was 46Ex".

@frazor77 said in post #96 that he's been having problems since he installed 48E2.

So you could try 46E8, 46E9 or 47EB. Or try stock firmware (it's probably OK to flash that straight from the GUI).

If I want to try the 46E8 for example, coming from my current latest version, do I have to go through again with the Asus utility or can I just use the GUI ?

 

[ColinTaylor]

If I want to try the 46E8 for example, coming from my current latest version, do I have to go through again with the Asus utility or can I just use the GUI ?

You can just use the GUI.

 

[Nite01]

You can just use the GUI.

Ok, I downgraded to the 46E9 (I also did a factory reset after the flash, and formatted JFFS 3 or 4 times (just in case )).
I will report back if the same issue reappears (hopefully not).

Thanks a lot, have a good evening !

 

[keturidu]

Ok, got AC66U autoreboot (with formated JFFS) again. Pastebin
version: 374.43_50D6j9527

[blush] Did that, and after 36 hours - no reboot. Will wait for a few days, just to be sure it won't restart after 56-60 hours, like Rahul_K mentions. Thanks.

 

[stalker780]

Hi,

Got a strange behavior using my Android phone as a 3G/4G modem.
It runs ResurrectionRemix Android Q. Set as modem by default on USB connection. This does not require any manual settings from Android side. Just plugin and use as modem.

It works fine as a Secondary WAN on my old N66U.
But router never connects to this WAN after reboot.
I tried to wait for about 30 minutes, but still no luck and no any actions in System log.
In Network map page USB modem is recognized and shows an icon of 3G.

Only after disconnecting USB cable and then in 10sec connecting it back again, router connects to Secondary WAN during about 1 minute, and works flawlessly till next power off.

Is it possible to fix this? Try to connect to USB modem periodically. Or after 1-2-5 minutes after router has loaded?
Router is used in my country house where power periodically goes offline, breaking internet connection.

Same behavior on 49E4 and 50E8 firmware.

I cannot paste logs here. Cloudflare blocks my message

 

[Nite01]

Ok, got AC66U autoreboot (with formated JFFS) again. Pastebin
version: 374.43_50D6j9527

I'm almost at 1 week running without any reboots using 46E9, maybe you should give that a try.

 

[tsanga]

I'm almost at 1 week running without any reboots using 46E9, maybe you should give that a try.

Has anyone given 47EB a try to check for stability on AC66U?

I’m also running 46E9, which is working very well.

 

[frazor77]

Updated to 374.43_50E8... formatted JFFS on next boot and rebooted manually. Not expecting a 'fix' for the reboots based on the changelog... but will report back anyway

 

[Nite01]

Updated to 374.43_50E8... formatted JFFS on next boot and rebooted manually. Not expecting a 'fix' for the reboots based on the changelog... but will report back anyway

Thanks, let us know how it goes.
I'm currently still running fine with 46E9 with an uptime of more than 2 weeks without reboots.

 

[john9527]

Updated to 374.43_50E8... formatted JFFS on next boot and rebooted manually. Not expecting a 'fix' for the reboots based on the changelog... but will report back anyway

I spent some time looking at commits, and couldn't see anything that would cause what your are seeing (especially not contained only to the AC66?).
Fail starts with a check of the http server (a unique check on this fork that actually tries to talk to the server instead of just checking that the process is running). It tries to restart the server 5 times then gives up.
Then, hours later the watchdog process is detected as crashed and the router reboots.

Only thing I could come up with is that something is possibly going crazy logging and you are running out of tmp space. I did see in one of the posted logs a lot of samba authentication errors (if it's posting in the syslog, then the other internal logs are definitely going crazy).

You may want to try keeping an eye on tmp space (run the 'df' command via ssh and look at tmpfs...it should only be arout 4-5% utilized).

 

[tsanga]

Only thing I could come up with is that something is possibly going crazy logging and you are running out of tmp space. I did see in one of the posted logs a lot of samba authentication errors (if it's posting in the syslog, then the other internal logs are definitely going crazy).

You may want to try keeping an eye on tmp space (run the 'df' command via ssh and look at tmpfs...it should only be arout 4-5% utilized).

I’m one user who has samba errors in my syslog. Currently I’m running 47EB for a few days without issues so far. I’ll keep watch on tmp usage. For now:

tmpfs                   119764      4664    115100   4% /tmp

 

[mark76]

Hi,
I also experience unexpected reboots on my RT-AC66U with this version of firmware.
Here is the part of system log, when the last reboot happened:

Spoiler: System Log:

...
Jul 31 15:28:44 (none) daemon.info dnsmasq-dhcp[577]: DHCPREQUEST(br0) 192.168.1.108 d0:ff:aa:aa:aa:d2
Jul 31 15:28:44 (none) daemon.info dnsmasq-dhcp[577]: DHCPACK(br0) 192.168.1.108 d0:ff:aa:aa:aa:d2 Huawei-P10
Jul 31 19:21:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:22:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:23:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:24:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:25:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:26:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:27:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:28:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:29:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:30:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:31:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:32:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:33:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:34:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:35:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:36:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:37:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:38:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:39:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:40:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:41:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:42:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:43:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:44:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:45:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:46:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:47:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:48:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:49:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:50:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:51:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:52:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:52:59 (none) user.info watchdog02: no watchdog, restarting
Jul 31 19:52:59 (none) user.info WEBDAV_Server: daemon is stopped
Jul 31 19:52:59 (none) user.info NFS_Server: daemon is stopped
Jul 31 19:53:00 (none) user.info MediaServer: daemon is stopped
Jul 31 19:53:00 (none) user.info FTP_Server: daemon is stopped
Jul 31 19:53:00 (none) user.info Samba_Server: smb daemon is stopped
Jul 31 19:53:00 (none) daemon.info dnsmasq[577]: exiting on receipt of SIGTERM
Jul 31 19:53:00 (none) daemon.info dnsmasq[574]: exiting on receipt of SIGTERM
Jul 31 19:53:00 (none) user.info stubby-proxy: stop stubby
...

EDIT: Didn't notice that there is newer version (50E8) of the firmware. I will update my router and monitor it for the issue.
Thank you @john9527 for your hard work and efforts you put to keep our old devices still reliable.

 

[frazor77]

Had another reboot overnight on 50E8. So that's an uptime of less than 48h

Log: https://pastebin.com/1QYjMsaf

admin@RT-AC66U:/tmp/home/root# df
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/root                20544     20544         0 100% /
tmpfs                   119760      4392    115368   4% /tmp
devfs                   119760         0    119760   0% /dev
/dev/mtdblock5           32768      1132     31636   3% /jffs

The only thing I can think of that's more 'advanced' in my setup is that I'm using AdGuard Home on a Home Assistant box (RPi4) so that is doing my DNS resolution, and alongside that I've enabled DNS based filtering as such:

 

[ColinTaylor]

Hi,
I also experience unexpected reboots on my RT-AC66U with this version of firmware.
Here is the part of system log, when the last reboot happened:

Spoiler: System Log:

...
Jul 31 15:28:44 (none) daemon.info dnsmasq-dhcp[577]: DHCPREQUEST(br0) 192.168.1.108 d0:ff:aa:aa:aa:d2
Jul 31 15:28:44 (none) daemon.info dnsmasq-dhcp[577]: DHCPACK(br0) 192.168.1.108 d0:ff:aa:aa:aa:d2 Huawei-P10
Jul 31 19:21:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:22:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:23:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:24:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:25:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:26:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:27:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:28:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:29:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:30:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:31:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:32:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:33:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:34:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:35:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:36:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:37:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:38:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:39:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:40:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:41:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:42:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:43:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:44:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:45:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:46:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:47:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:48:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:49:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:50:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:51:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:52:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:52:59 (none) user.info watchdog02: no watchdog, restarting
Jul 31 19:52:59 (none) user.info WEBDAV_Server: daemon is stopped
Jul 31 19:52:59 (none) user.info NFS_Server: daemon is stopped
Jul 31 19:53:00 (none) user.info MediaServer: daemon is stopped
Jul 31 19:53:00 (none) user.info FTP_Server: daemon is stopped
Jul 31 19:53:00 (none) user.info Samba_Server: smb daemon is stopped
Jul 31 19:53:00 (none) daemon.info dnsmasq[577]: exiting on receipt of SIGTERM
Jul 31 19:53:00 (none) daemon.info dnsmasq[574]: exiting on receipt of SIGTERM
Jul 31 19:53:00 (none) user.info stubby-proxy: stop stubby
...

EDIT: Didn't notice that there is newer version (50E8) of the firmware. I will update my router and monitor it for the issue.
Thank you @john9527 for your hard work and efforts you put to keep our old devices still reliable.

What firmware version were you using?

You appear to have run out of memory. What add-ons have you installed?

 

[john9527]

Hi,
I also experience unexpected reboots on my RT-AC66U with this version of firmware.
Here is the part of system log, when the last reboot happened:

Spoiler: System Log:

...
Jul 31 15:28:44 (none) daemon.info dnsmasq-dhcp[577]: DHCPREQUEST(br0) 192.168.1.108 d0:ff:aa:aa:aa:d2
Jul 31 15:28:44 (none) daemon.info dnsmasq-dhcp[577]: DHCPACK(br0) 192.168.1.108 d0:ff:aa:aa:aa:d2 Huawei-P10
Jul 31 19:21:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:22:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:23:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:24:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:25:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:26:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:27:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:28:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:29:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:30:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:31:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:32:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:33:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:34:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:35:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:36:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:37:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:38:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:39:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:40:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:41:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:42:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:43:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:44:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:45:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:46:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:47:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:48:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:49:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:50:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:51:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:52:15 (none) daemon.err dnsmasq-dhcp[577]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60 s)
Jul 31 19:52:59 (none) user.info watchdog02: no watchdog, restarting
Jul 31 19:52:59 (none) user.info WEBDAV_Server: daemon is stopped
Jul 31 19:52:59 (none) user.info NFS_Server: daemon is stopped
Jul 31 19:53:00 (none) user.info MediaServer: daemon is stopped
Jul 31 19:53:00 (none) user.info FTP_Server: daemon is stopped
Jul 31 19:53:00 (none) user.info Samba_Server: smb daemon is stopped
Jul 31 19:53:00 (none) daemon.info dnsmasq[577]: exiting on receipt of SIGTERM
Jul 31 19:53:00 (none) daemon.info dnsmasq[574]: exiting on receipt of SIGTERM
Jul 31 19:53:00 (none) user.info stubby-proxy: stop stubby
...

EDIT: Didn't notice that there is newer version (50E8) of the firmware. I will update my router and monitor it for the issue.
Thank you @john9527 for your hard work and efforts you put to keep our old devices still reliable.

What firmware version were you using?

You appear to have run out of memory. What add-ons have you installed?

Bingo...../var is a link to /tmp/var which resides in the tmpfs space. So something is eating up the space.
Let me think a bit.....may need to do a debug build that removes the restart to we can see what it is.

Another option might be to open an ssh session and run the following

while true; do du -ah /tmp | grep -v "mnt" | sort -n -r | head -n 10; sleep 60; done;

This will write the top ten largest files in /tmp to the console every minute.