Self Signed Certificate, Key and CA

self-signed-certificate-key-ca.md

Create Root CA (Done once)

Create Root Key

Attention: this is the key used to sign the certificate requests, anyone holding this can sign certificates on your behalf. So keep it in a safe place!

openssl genrsa -out rootCA.key 4096

Create and self sign the Root Certificate

openssl req -x509 -new -nodes -key rootCA.key -sha256 -days 1024 -out rootCA.crt

Here we used our root key to create the root certificate that needs to be distributed in all the computers that have to trust us.

Create a certificate (Done for each server)

This procedure needs to be followed for each server/appliance that needs a trusted certificate from our CA

Create the certificate key

openssl genrsa -out server.key 2048

Create the signing (csr)

The certificate signing request is where you specify the details for the certificate you want to generate. This request will be processed by the owner of the Root key (you in this case since you create it earlier) to generate the certificate.

Important: Please mind that while creating the signign request is important to specify the Common Name providing the IP address or domain name for the service, otherwise the certificate cannot be verified.

Automation Friendly Method

This method is suitable for use in your automation :) .

openssl req -new -sha256 -key server.key -subj "/C=US/ST=CA/O=Cloudify/CN=server" -out server.csr

Generate the certificate using the server csr and key along with the CA Root key

openssl x509 -req -in server.csr -CA rootCA.crt -CAkey rootCA.key -CAcreateserial -out server.crt -days 500 -sha256

In order to install a cluster node, you need:

rootCA.crt, server.crt, server.key