# Bootnode ## Options - ```listen-addr```: listening address of bootnode (:) - ```v5```: Enable UDP v5 - ```log-level```: Log level (trace|debug|info|warn|error|crit) - ```nat```: port mapping mechanism (any|none|upnp|pmp|extip:) - ```node-key```: file or hex node key - ```save-key```: path to save the ecdsa private key - ```dry-run```