inet_interfaces parameter specifies all network interface
addresses that the Postfix system should listen on; mail addressed
to "user@[network address]" will be delivered locally,
as if it is addressed to a domain listed in $
You can override the
inet_interfaces setting in the Postfix
master.cf file by prepending an IP address to a server name.
The default is to listen on all active interfaces. If you run
mailers on virtual interfaces, you will have to specify what
interfaces to listen on.
IMPORTANT: If you run MTAs on virtual interfaces you must
inet_interfaces values for the MTA that receives
mail for the machine itself: this MTA should never listen on the
virtual interfaces or you would have a mailer loop when a virtual
MTA is down.
Example: default setting.
inet_interfaces = all
Example: host running one or more virtual mailers. For
each Postfix instance, specify only one of the following.
inet_interfaces = virtual.host.tld (virtual Postfix)
inet_interfaces = $
myhostname localhost... (non-virtual Postfix)
Note: you need to stop and start Postfix after changing this