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- Install a new node with the role "role::base"
- Make sure to add the puppetdb hostname in the nodes hiera file under the key "profile::puppet::altnames". Then regenerate the puppet client certificates for this node, so that the node have a certificate valid for both its hostname and the common puppetdb hostname.
- Install the role "role::puppet::db"
- Wait for, or trigger, a puppet run on the loadbalancers, which will include the new server.