CSR erstellen

openssl req -nodes -new -keyout <file.key> -newkey rsa:4096 -sha256 -out <file.csr>

CSR Config File erstellen

vim heisl.org_20210622.conf

[req]
distinguished_name = req_distinguished_name
req_extensions = v3_req
prompt = no
[req_distinguished_name]
C = AT
ST = Vienna
L = Vienna
O = Heisl
OU = IT
CN = heisl.org
[v3_req]
keyUsage = keyEncipherment, dataEncipherment
extendedKeyUsage = serverAuth
subjectAltName = @alt_names
[alt_names]
DNS.1 = heisl.org
DNS.2 = www.heisl.org

CSR Erstellen

openssl req -new -sha256 -nodes -out heisl.org_20210622.csr -newkey rsa:4096 -keyout heisl.org_20210622.conf.key -config heisl.org_20210622.conf

CSR Checken

openssl req -text -noout -verify -in heisl.org_20210622.csr

verify OK
Certificate Request:
...
...
X509v3 Subject Alternative Name:
DNS:heisl.org, DNS:www.heisl.org
...
...