Create CSR (Certificate Sign Request)

Create CSR config file 
 export fqdn="project.customer.com"
vi ${fqdn}.csr.conf
 
 content 
 [ req ]
default_bits = 2048
default_md = sha256
prompt = no
encrypt_key = no
distinguished_name = dn
req_extensions = req_ext

[ dn ]
C = country-abbreviation
ST = project
L = location
O = org
OU = org-unit
CN = project.customer.com

[ req_ext ]
subjectAltName = @alt_names

[ alt_names ]
DNS.1 = www.project.customer.com
DNS.2 = stg-project.customer.com
DNS.3 = www.stg-project.customer.com
 
 Generate CSR 
 export fqdn="project.customer.com"
openssl req \
 -new \
 -newkey rsa:4096 \
 -nodes \
 -config ${fqdn}.csr.conf \
 -keyout ${fqdn}.key \
 -out ${fqdn}.csr
 
 Verify CSR 
 openssl req \
 -in ${fqdn}.csr \
 -noout \
 -text