Connectalias, connectcanonical Channel Options

Envelope address rewriting upon message dequeue
The MTA normally rewrites addresses as it enqueues messages to its channel queues. No additional rewriting is done during message dequeue. This presents a potential problem when host names change while there are messages in the channel queues still addressed to the old name.

The  option tells the MTA to simply deliver to whatever host is listed in the recipient address. This is the default. tells the MTA to compare the recipient envelope address domain with the channel host proper names, and if the domain name matches one of the channel&#x27;s host proper names, then connect to the host name corresponding to that host proper name. For instance, if a channel is defined (in pmdf.cnf/imta.cnf format) as: tcp_scanner smtp connectcanonical ...rest-of-keywords... SCANNER-DAEMON scanner1.domain.com host1.domain.com scanner2.domain.com host2.domain.com then an address of  that rewrites to the   channel will be routed out to the host scanner1.domain.com, rather than to host1.domain.com as would occur by default.

should only be used specifically to deal with problems with queued messages---it may have unintended effects on other message traffic.

See also:
 * TCPIP connections and DNS lookups channel options
 * Channel options