sudo openssl req -new -newkey rsa:2048 -nodes -keyout server.key -out *.freesoftwareservers.csr 

It is strongly recommended to fill all the required fields in. If a field is left blank, the CSR can be rejected during activation. For certificates with domain validation it is not mandatory to specify “Organization” and “Organization Unit” -you may fill the fields with ‘NA’ instead. In the Common Name field you need to enter the domain name the certificate should be issued for.

Please use only symbols of English alphanumeric alphabet. Otherwise the CSR can be rejected by a Certificate Authority.

If the certificate should be issued for a specific subdomain, you need to specify the subdomain in ‘Common Name’. For example ‘sub1.ssl-certificate-host.com’.

In case of Wildcard certificates, the domain name should start with an asterisk as in ‘*.ssl-certificate-host.com

Once all the requested information is filled in, you should have *.csr and *.key files in the folder where the command has been run.

*.csr file contains the CSR code that you need to submit during certificate activation. It can be opened with a text editor. Usually it looks like a block of code with a header: “-----BEGIN CERTIFICATE REQUEST----“ It is recommended to submit a CSR with the header and footer.

*.key file is the Private Key, which will be used for decryption during SSL/TLS session establishment between a server and a client. It has such a header: “-----BEGIN RSA PRIVATE KEY-----“. Please make sure that the private key is saved as it will be impossible to install the certificate without it on the server afterwards.

https://www.namecheap.com/support/knowledgebase/article.aspx/9446/0/apache-opensslmodsslnginx