I want to set up secure TLS for my docker hosts as described here which describes creating your own Public Key Infrastructure (PKI). For production servers it is inadvisable to use your own Certificate Authority. Are there any online Certificate Authorities that can provide the public/private keys (.pem and .csr files) for me? I have been looking at Lets Encrypt, as I know they can provide SSL certificates, but I cannot find any guidance on providing a PKI.
Edit:
This is the setup I'm attempting to create:
Can Let's Encrypt or any other online service, provide the necessary key/cert files as represented in this image.
You can use Ascertia services to setup your pki structure. https://www.ascertia.com/ They have a full PKI standard service for CA and Key Management.