Use NPM to create a certificate with additional DNS entries

[wagnbeu0]

How can I use NPM to create a certificate with additional DNS entries? For example:
I am using NPM to connect to an NGINX Proxy Manager. The certificate which NPM created should now also incldue the 1jk.myfritz.net, fritz.box and also my official dns name. How can I archive it ?

[dfbustosus]

NPM can request one certificate containing multiple SANs. Open Certificates → Add Certificate → Let's Encrypt via HTTP, enter each hostname separately under Domain Names, test, and save. Then assign the certificate to the relevant Proxy Host.

Let's Encrypt must validate every hostname. 1jk.myfritz.net can only be included if that exact public hostname reaches NPM on port 80. fritz.box cannot normally be validated by a FRITZ!Box owner: local DNS resolution does not give you control of the public fritz.box domain, so including it will make the entire order fail.

Use names under a domain you control, optionally with split DNS for local access. For a private-only name, use a private CA and import the certificate as a custom certificate. Existing certificate SANs cannot be edited in NPM; create a replacement certificate.

Reference: https://letsencrypt.org/docs/challenge-types/