503 bad gateway means there is a drop in the middle mostly, sometimes if the origin server cant reply or achieve the target,
so the symptoms is indicate 3 things in general
- problem with the server itself,
- problem with the firewall or closed port,
- problem with the DNS referrals
you can simply check if “send” service is running by the command by the command:
yunohost service status send
or by simply go to your admin panel
you’re declarations about two things is not clear,
once you got "
No domain registered with DynDNS ."
that is indicate you don’t host your domain with yunohost dns’s?
are you using your own domain? something you got from another service than yunohost dyndns?
if so how youre updating your domains?
you should have another dynamic dns client running on your server, you need to check if that dynamic dns is running normally and updating all your name records fully,
and what do you mean by secondary domain?
do you mean subdomain or secondary domain?
subdomain its an alias for the main domain,
do a deeper test to your router,
go to your router interface → port forwarding, and open all ports from 22 to
20000 in a range, just one line, in most of routers you will be able to insert a port range instead of one by one,
there are situations the router has an open port but its drops the traffic for some reasons, cause the router itself has its own firewall,
so the only way to do it is to open that whole range and disable your router’s firewall for testing purposes,
i don’t know what router do you have but its should be simple,
after you will open a port range stop your router’s firewall you will be able to test if there are any drops on your server again,