How create a certificate request

Product:
OPENSSL
Linux Centos

Problem:
How create a SSL (TLS) request for a server that need a certificate?

Suggested Solution:

Install openssl on your Centos Linux with command:

yum install openssl

Create a folder to work in mkdir /ibm

Go to that folder cd /ibm

Create a text file with a text editor like; nano san.txt

[ req ]
default_bits       = 2048
distinguished_name = req_distinguished_name
req_extensions     = req_ext
prompt             = no
[ 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   = servername
DNS.2   = servername.domain.com
DNS.3   = dnsalias.domain.com

Save above text in the file after you change to your server-names.
openssl req -out /ibm/request.csr -newkey rsa:2048 -nodes -keyout /ibm/privateKey.pem -config /ibm/san.txt
Above will give a new server private key and a certificate request for a cert.

Check the request with command:

openssl req -text -noout -verify -in request.csr

Check the private key with command:

openssl rsa -in privateKey.pem -check

The private-key should only be stored on the server where it should be used.
The certificate request you copy and paste to your Certificate Authority to generate your certificate.