Hi, for clarity, the simplest thing is to use an FQDN which is managed by 3cx, not a custom FQDN that you manage. So this might be "yourOrgName.3cx.ca" or "yourOrgName.3cx.OtherSuffixHere" (ie, 3cx have a variety of suffix / FQDN / depending on your region). This is just built-in to 3cx, there is no 'cost' for this DNS stuff.
Assuming you deploy your 3cx instance with the FQDN that 3cx have assigned / with your collaboration at setup
then the SSL cert renew is 100% automatic and built in under the hood
and
if you choose to not go that route, you are looking at unsupported config, I think, and need to either
manually update certs yourself
or
manually install certs yourself (ie, purchased non-free certs)
or
figure out your own way to make the update happen automatically. This might be a manual config of certbot and letsencrypt - stuff - maybe - depending on your comfort / familiarity with various solution/options.
for all the 3cx instances that I manage on behalf of my clients, I simply go with the default - pick the name - at install time - go with vanilla 3cx DNS - everything is automatic, zero effort, smooth operating. ie, I can recommend that method.
Tim
