I have set myself up as a Certicate Authority so I can sign certificates I need for development. I have imported my CA certificate in my browsers so certificates I sign are accepted without question
As NOT the CA, I made myself a Certificate Signing Request containing a Common Name for one internal domain name, and added about 10 other (internal) domain names with the objective of having myself as CA sign it. The CSR has those names - I can see them when I look at it.
I signed the certificate as CA, using my own openssl.cnf file that I normal use for my single domain certificates and it appears to have stipped out all the AltSubjectNames, so the signed certificate I have produced is only good for the one domain in the CN field. My browsers complain when I try and use it for one of the other domains.
I think I need to adjust the extension in my CAs openssl.cnf file to not strip them out. The man page for CA points me at the man page for x509v3_config. But the reading of this is obscure and I can't figure out what to do.
Searching the internet for solutions came up with nothing - there are plenty of descriptions as to how to get the CSR, but absolutely nothing about how a CA can carry over the AltSubjectNames in the CSR into the final Certificate.
How is it done?