esmtprc - esmtp configuration file.
A esmtp configuration file consists of several options. The options
format is:
keyword=value
The equal sign is optional and can be replaced by whitespace. The
value may be enclosed in simple or double quotes, in which case special
characters can be escaped as in normal C strings.
Comments are delimited by the '#' character up to the newline
character.
hostname
Set SMTP host and service (port).
The format is:
host.example.org[:service]
With no whitespace surrounding the colon if service is
specified. service may be a name from /etc/services or a decimal
port number. If not specified the port defaults to 587.
Note (from libESMTP documentation): the default port number is
set to 587 since this is the port that should be used for mail
submission, see RFC 2476. By choosing this default now, the API
does not change behavior unexpectedly in the future as use of
the new standard becomes commonplace. The host-port notation
simplifies things for the application, the user can type
"localhost:smtp" or "localhost:25" where the application expects
a host name.
username
Set the username for authentication with the SMTP server.
Do NOT set the username and password in the system configuration
file unless you are the only user of this machine. Esmtp is not
run with suid privileges therefore the system configuration file
must be readable by everyone. If your SMTP server requires
authentication and you are not the only user then specify your
personal SMTP account details in the user configuration file.
password
Set the password for authentication with the SMTP server.
starttls
Whether to use the StartTLS extension.
It can be one of enabled, disabled or required. It defaults to
disabled.
certificate_passphrase
Set the certificate passphrase for the StartTLS extension.
helo Set the hostname to identify as when sending HELO or EHLO
commands. (This is a per identity option, as it should be the
name you are seen as from the connected host, which may vary
with host to host due to NAT or different naming schemes).
qualifydomain
Make all local addresses to remote ones by adding @ and this
name.
force sender
Set a "Sender:" header and ignore those in the message. "%u"
will be replaced with the username. "%%" by "%".
force reverse_path
Set the envelope from address. The address given to -f will only
be used as "From:" when the message contains none. "%u" will be
replaced with the username. "%%" by "%".
message_id
Whether to set the Message-ID field of the message before
sending. Normally the receiving MTA sets the Message-ID if
missing, so you can turn this off if your sending host does not
have a fully qualified domain name.
Allowed values are either enabled or disabled. It defaults to
enabled
preconnect
Shell command to execute prior to opening an SMTP connection.
This may be useful in conjunction with application-level
transports (e.g. ssh with its port-forwarding functionality) to
secure the SMTP connection. Esmtp will wait for the command to
exit before proceeding. If the command returns a non-zero
status, delivery will be aborted.
identity
Define an identity.
An identity is a set of options associated with a given address.
For example:
identity = [email protected]
hostname = smtp.somewhere.com:25
username = "myself"
password = "secret"
Identities are be selected by the address specified in the -f
flag. You can have as many you like.
The options in the global section (up to the first identity
option) constitute the default identity. If no options in the
global section are given then the first defined identity is
taken as the default one.
Note that the default identity settings are not shared by the
other identities. Everything (username, password, etc.) must be
specified for every identity even if they don't differ from the
default identity.
mda Set the Mail Delivery Agent (MDA).
Esmtp relies upon a MDA for local mail delivery, i.e., addresses
without a '@' character. A non-zero error status tells esmtp
that delivery failed.
The local delivery addresses will be inserted into the MDA
command wherever you place a %T. The mail message's From
address will be inserted where you place an %F.
Some common MDAs are "/usr/bin/procmail -d %T",
"/usr/bin/deliver" and "/usr/lib/mail.local %T".
force_mda
Force mail to be delivered by the MDA.
When set, any mail from anywhere to anywhere will instead be
delivered to the value of force_mda. It will also only be
delivered locally, via the mda. This will let you have a very
minimal mail set-up, which can ONLY handle local mail.
For example:
mda = "procmail -d %T"
force_mda = "someuser"
esmtp(1)
Jos Fonseca
ESMTPRC(5)
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