> Nothing stops you from loading your key into a fleet of them and scaling horizontally just like you scale anything else. Isn't having one key the root of the

> Nothing stops you from loading your key into a fleet of them and scaling horizontally just like you scale anything else. Isn't having one key the root of the problem? If you've got one key, it has to be transferred to each HSM module, which means it's going to be in their deploy code. My understanding is that the safe way to scale PKI is to have an HSM generate a key internally, and have that key be signed by a CA in a different HSM, so private key material never leaves any HSM. I guess you're saying that SSH RSA host keys support this, but I'm only familiar with doing it using looks up correct terminology X.509 certificates like for HTTPS.