When tls auth-key, tls crypt-key or shared-secret-key references a name that isn't configured under pki openvpn shared-secret, commit fails with There are no openvpn shared-secrets in PKI configuration. It is raised from multiple paths (interfaces_openvpn.py:223 for the PSK shared-secret-key, :290 for tls auth-key/crypt-key) and doesn't say which leaf is at fault and it points at PKI instead of the offending interface line.

run generate pki ca install ovpn-ca

set interfaces openvpn vtun1 mode server
set interfaces openvpn vtun1 server subnet 10.20.30.0/24
set interfaces openvpn vtun1 tls ca-certificate ovpn-ca
set interfaces openvpn vtun1 tls auth-key NONEXISTENT
commit