With 3CX V15 we’ve switched to a new server, NGINX, which allows for a rock solid and more secure configuration while at the same time it steps up the protection of the provisioning directory.
Additionally, NGINX makes the replacement of a self-owned generated certificate simpler than ever. Note, this procedure does not cover the switch from a 3CX managed domain and certificate to a self-owned domain! This will require a reinstall including a release of the license key bound FQDN! More on this can be found here: https://www.3cx.com/docs/fqdn-management-allocation/
- PBX installed with own domain FQDN (e.g. pbx.mybusiness.com)
- Presented cert at installation time to correctly convert the FQDN pbx.mybusiness.com
- New cert still covers the FQDN pbx.mybusiness.com
Read the guide on how to renew your SSL certificate in 3CX V15.