**- Install OpenSSH for Windows or use linux with openSSH** 

**- Create a configuration file with the following information:**

[req] \\
default_bits       = 2048 \\
prompt             = no \\
default_md         = sha256 \\
req_extensions     = req_ext \\
distinguished_name = dn \\

[dn] \\
C  = LU \\
ST = Luxembourg \\
L  = Luxembourg \\
O  = Organization \\
CN = server.organization.local \\

[req_ext] \\
subjectAltName = @alt_names

[alt_names] \\
DNS.1 = server.organization.local \\
DNS.2 = altservername.organization.local \\
IP.1  = 192.168.1.1


//**Savit it as config.cnf**//

**- Open CMD, navigate to the folder where you saved your cnf file and type the following:**
<cli>openssl req -new -nodes -out server.csr -newkey rsa:2048 -keyout server.key -config config.cnf</cli>
This will create 2 files: 
- server.csr
- server.key