Messages

If you are using mDNS, don't use port 5353 for DNS because it will conflict with mDNS.

+1

Use anything but 5353

It's an alias for something in AWS. Might you have a blocklist configured in Unbound which may be blocking AWS?

Name:    comms-servers-load-balancer-41abfb75b750f680.elb.eu-west-2.amazonaws.com
Addresses:  35.178.236.174
          18.170.183.170
          13.42.129.212
Aliases:  comms.givenergy.cloud

You may need to create a cron job to handle it

Is the "Default allow LAN IPv6 to any rule" for your LAN interface in place and enabled? Yes. It is at the bottom of the stack of auto-generated rules, along with the IPv4 rule that does the same thing.

Check the setting at the bottom of Interfaces -> Settings regarding the "Allow IPv6" checkbox too

Hopefully, you haven't disabled "Startup/Shutdown Sound" at the bottom of "System: Settings: Miscellaneous"

I have only the one

os-zerotier (installed)   1.3.2_4

I see many starting to use the YYYY.MM.# or similar format these days for software release identification. It alleviates the need to investigate a version number to determine its release date which can be annoying. In fact, we moved to this formatting in my company last year.