Node SSL Cert error code -1

Hello Support,

To a test node version 6.3.1, we added SSL with the following configuration in the node service config:

Environment=CONCORDIUM_NODE_GRPC2_LISTEN_ADDRESS=0.0.0.0
Environment=CONCORDIUM_NODE_GRPC2_LISTEN_PORT=20001
Environment=CONCORDIUM_NODE_GRPC2_X509_CERT=/var/concordium/testnet-node-all-cert.pem
Environment=CONCORDIUM_NODE_GRPC2_CERT_PRIVATE_KEY=/var/concordium/testnet-node-cert-pk.pem

The node service fails with an exit=1 error, but there are no helpful error messages.

Could you please assist us in identifying the cause of the error?

Thank you.