If you choose this service, a new dialog is opened. Fill at least in the required fields, then Save:
- Visible full qualified hostname: (required) The fully qualified host name. The internet hostname of this mail system.
- Max mail header size (KB): The maximum amount of memory in Kbytes for storing a message header. If the header is larger, the excess is discarded. Default value is zero, that defines no limit.
- Max mailbox size (KB): The maximum size of any local individual mailbox or maildir file. Default value is zero, that defines no limit. This limit must not be smaller than the message size limit.
- Max message size (KB): The maximum size in bytes of a message, including envelope information. Default value is zero, that defines no limit.
- Relay host: Relay messages to following host. The next-hop destination of non-local mail; overrides non-local domains in recipient addresses. Specify a domain name, hostname, hostname:port, [hostname]:port, [hostaddress] or [hostaddress]:port. The form [hostname] turns off MX lookups.
- Local networks: The list of “trusted” remote SMTP clients that have more privileges than “strangers”. Specify a list of network addresses or network/netmask patterns, separated by commas and/or whitespace. Continue long lines by starting the next line with whitespace.
127.0.0.0/8 22.214.171.124/28 [::1]/128 [2001:240:587::]/64
- Restrictions for sender: Optional restrictions that the Postfix SMTP server applies in the context of a client MAIL FROM command. The default is to permit everything. Restrictions are applied in the order as specified; the first restriction that matches wins.
- Restrictions for recipient: Optional restrictions that the Postfix SMTP server applies in the context of a client RCPT TO command.
Domains and routing
- Domains to accept mail for: The list of domains that are delivered via the local_transport mail delivery transport. Do not specify the names of virtual domains - those domains are specified elsewhere. Do not specify the names of domains that this machine is backup MX host for. By default, the Postfix SMTP server rejects mail for recipients not listed.
- Transport: Specifies a mapping from email addresses to message delivery transports and next-hop destinations.