Assuming that your domains are the following 4 domains
www.example.com
www.example1.com
www.example2.com
www.example3.com
www.example4.com
Step 1:
#Open your terminal app and create a file called sancert.cnf
Step 2:
#In this new file you just created insert the following lines of text.
[ req ]
default_bits = 2048
distinguished_name = req_distinguished_name
req_extensions = req_ext
[ req_distinguished_name ]
countryName = Country Name (2 letter code)
stateOrProvinceName = State or Province Name (full name)
localityName = Locality Name (eg, city)
organizationName = Organization Name (eg, company)
commonName = Common Name (e.g. server FQDN or YOUR name)
[ req_ext ]
subjectAltName = @alt_names
[alt_names]
DNS.1 = www.example.com
DNS.2 = www.example1.com
DNS.3 = www.example2.com
DNS.4 = www.example3.com
DNS.5 = www.example4.com
Step 3:
Save your file and go back to your terminal app.
Step 4:
# In your terminal, type the following command (in the same dir as the file you just created)
$ openssl req -out sslcert-example.csr -newkey rsa:2048 -nodes -keyout sslcert-example.key -config sancert.cnf
This will create 2 files.
1. sslcert-example.csr
2. sslcert-example.key
