DMZ and something like DYNDNS

[Jack V]

I had my cable modem in bridge mode for a long time and used Dynamic DNS service of Namecheap without worries.

Now I changed my setup a bit and now the bridge mode is not handy for me right now. The OPNsense router is put in via the modem in DMZ. This works great, except of course when the provider changes the external modem IP then I am lost and can't get into the network any more, this has not happened yet but will eventually.

Is there something I can do with OPNsense and a external service like DYNDNS or Namecheap that can detect my external modem IP and update that to a dns record?

[sorano]

Is there something I can do with OPNsense and a external service like DYNDNS or Namecheap that can detect my external modem IP and update that to a dns record?

Well, by default OPNsense dyndns will use the IP on the monitored interface so if your interface is behind NAT it will not use your public IP.

I guess workarounds could be to run dyndns client in your cable modem if it has that possibility. Otherwise you could run the dyn updater client on a host/vm on your lan. Dyn updater can check your external IP and use that for your DNS record.