TP-link archer C6 v2 random reboots

Ok so I flashed OpenWrt on my device roughly a week ago because I needed ubus compatibility, however since then I experienced several random reboots often in the middle of the night. To solve it I tried to setup a remote syslog to catch every event but I don't know how to read it. Here it is: https://pastebin.com/Y3WktRDj

As you can see the time between each reboot is different and I would say that it's not predictable. The system log ( not the kernel, the other one ) is just filled with "Oct 18 14:26:37 OpenWrt dnsmasq-dhcp[1]: DHCP packet received on eth0.2 which has no address" and some requests from plex blocked by dnsmasq.

Thanks in advance.

There isn't much information in the syslog. Those messages in the system log are not connected to reboots. Can you make sure that there is no power brownout/blackout or issue with the power supply?

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These messages can be suppressed by adding the line except-interface=eth0.2 to /etc/dnsmasq.conf using vim or nano.
It's the same on my Archer C50.

The power brick is the stock one and the device never behaved this way with the stock firmware, so I don’t really know what to do.

I've had some issues with OpenWRT 22.03.1. You can now update to 22.03.2 which has important security fixes, plus might help with you problem.

Ok thanks I will try it

I flashed the new firmware but it keeps rebooting randomly. I don’t know what to do. I think I’m going to do a factory flash to wipe everything.

Try a new/larger power supply as suggested by @trendy. Your current supply could be marginal or failing. If the supply is, for example, 12V 1.0A, try one rated at 12V 1.5A if you have that around (or if you’re buying a new one) to give some operating margin.

You would surprised how often power supply issues crop up like this.

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Ok so I spent the last week reading on the forum about all sort of bugs causing OpenWrt to crash. One night while trying to play LoL, the 5Ghz band got completely obliterated but the device didn't reboot, so I successfully caught the kernel logs and found out that the router run out of memory and started killing everything. So I began to search online and discovered that there is a -smallbuffers version of the antenna drivers made for low-memory devices. I used that information to build a custom image swapping the normal drivers with the -smallbuffers one and in the last 5 days it didn't reboot once. The only remaining problem is that sometimes the 5Ghz band randomly gets no internet connection while the 2.4Ghz one continues to work. The logs doesn't show anything suspicious for now.