They do not, for example, reject on the basis of the domain part
of the hostname, nor do they reject on the basis of the individual host IP addresses.
Beginning withV8.14 sendmail, any macro that is given a value as part of this check_
relay rule set will have that value maintained by sendmail for the duration of the current
SMTP session. To illustrate, consider a policy that allows multiple recipients for
local delivery, but only one recipient per envelope when mail is relayed. A rule inside
this check_relay rule set could, for example, define a flag:
Kstorage macro
R$* $: $(storage {WeAreRelaying} $@ TRUE $)
This rule stores the constant value TRUE in the ${WeAreRelaying} macro. Later, when
the check_compat rule set (?§7.1.5 on page 259) is called, the flag will cause sendmail
to limit the number of allowed recipients.
Note that the rules in the Local_check_relay and check_relay rule sets cannot be
tested in rule-testing mode because that mode wrongly interprets the expression $|
* Actually, the message is not printed; instead, the SMTP daemon goes into a ???reject everything??? mode. This
prevents some SMTP implementations from retrying the connection.
?? Actually, $#anything will have the same effect, but you should use $#OK only to remain compatible with
future releases of sendmail.
This is the Title of the Book, eMatter Edition
Copyright ?© 2007 O??™Reilly & Associates, Inc.
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