v3.1 configuration example

Postfix sender-dependent transport

Review and adapt this example to your topology, product version and security requirements.

sender_dependent_default_transport_maps = hash:/etc/postfix/sender_transport

# /etc/postfix/sender_transport
@example.net smtp:[relay1.example.net]:25
@alerts.example.net smtp:[relay2.example.net]:25

Important: replace example addresses, credentials, hostnames and paths. Validate syntax before deployment.