Unable to provision using custom RancherOS install

Hello,

I’m using Rancher 2.3.5 in a HA setup. Provisioning RancherOS nodes using an ISO file and the vSphere driver works fine. I have created a VMware template by installing RancherOS from the ISO and using a cloud-config.yml file where SSH keys from the rancher nodes are added. When I try to provision clusters using this VMware template, it always stops at “Waiting for SSH to be available”. I can still SSH to the provisioned node from the rancher nodes using the SSH keys.

In the SSHD log on the provisioned node I see:

Connection closed by authenticating user docker 10.1.28.23 port 42993 [preauth]
Failed publickey for docker from 10.1.28.23 port 8766 ssh2: RSA SHA256:xxxxxxxxxxxxxxxxxxxxxxxxxxxx

The reported SHA256 hash of the public key is not one of the keys I add in cloud-config.yml. Clearly Rancher is using another SSH key to access the node during provisioning, but which one? Or am I missing some other step in this configuration?

Thanks in advance,
Daniel