Certificate isssue after new installation

I run a fresh install, ad create a new domain.
Te first time I logon, and I’m not satisfied with the CA common name. While their was nothing ells on the server than the default install, I change the CA certificate, on this server. After the reboot I receive the error below, when I run the system check: Found invalid certificate ‘/etc/simplesamlphp/ucs-sso.domainname.org-idp-certificate.crt’:

Hopefully, one off you can help me to resolve this issue.

Hi @goudduif,

please check your UCR settings against your needs. If no value is given the default value is used.

ucr search --brief --value "(.crt|.pem)"

Also you might look at the certificate itself:

openssl x509 -in /etc/simplesamlphp/ucs-sso.domainname.org-idp-certificate.crt -noout -text | less

Look for the Subject, Validity and SAN (Subject Alternative Name).

Kind Regards