The optional transport file specifies a mapping from domain hierarchies to
message delivery transports and/or relay hosts. The mapping is used by the
trivial-rewrite(8) daemon.
The format of the transport table is as follows:
- domain mapped to.. transport:nexthop: Mail
for domain is delivered through transport to nexthop.
- .domain mapped to.. transport:nexthop: Mail
for any subdomain of domain is delivered through transport to nexthop.
Note: transport map entries take precedence over domains specified in the
mydestination parameter. If you use the optional transport map, it may
be safer to specify explicit entries for all domains specified in
mydestination, for example:
- hostname.my.domain ... local:
- localhost.my.domain ... local:
The interpretation of the nexthop field is transport dependent. In the case of
SMTP, specify host:service for a non-default server port, and use
[host] or [host:port] in order to disable MX (mail exchanger)
DNS lookups. The [] form can also be used with IP addresses instead of
hostnames.