I have done this many times but I never got to write about it and I felt that I should write about it after I helped a friend of mine with this.


It doesn't matter which operating system you're going to do this on as long as you have openssl installed in your system, you should be fine.

All you have to do is just create a simple configuration file and give it a name like multiple-domains.cnf:

default_bits       = 2048
distinguished_name = req_distinguished_name
req_extensions     = req_ext

countryName         = [COUNTRYCODE]
stateOrProvinceName = [STATE]
localityName        = [LOCALITY]
organizationName    = [ORGANIZATION]
commonName          = website.com

subjectAltName = @alt_names

DNS.1 = website.org
DNS.2 = wesbite.ae
DNS.3 = wesbite.co.uk

Save the file and copy-paste this into your command prompt or terminal:

openssl req -out <your-csr-name>.csr -newkey rsa:2048 -nodes -keyout <your-private-key-name>.key -config multiple-domains.cnf

Once executed, it should be generated for you and if not, verify your configuration file for any typos.

Hope this helps you out!