I have this in my 20-lmtp.conf file and created passdb-file, this should be enough to route a message to svr1? The port 24 is reachable from the proxy.

bash-5.0# cat 20-lmtp.conf lmtp_proxy = yes

protocol lmtp { # Space separated list of plugins to load (default is global mail_plugins). passdb { driver = passwd-file args = /etc/dovecot/special-passdb default_fields = proxy=y host=svr1 } }

bash-5.0# cat /etc/dovecot/special-passdb test:password:1000:1000:(gecos):home:/bin/false:host=svr1