System Administration Guide: Network Services

Additional and Revised FEATURE() Declarations in Version 8.13 of sendmail

The following table describes the added and revised FEATURE() declarations. This m4 macro uses the following syntax.

FEATURE(`name', `argument')
Table 14–18 FEATURE() Declarations Available in Version 8.13 of sendmail

Name of FEATURE()



Works with the access_db rule set to check the number of incoming SMTP connections. For details, see /etc/mail/cf/README.


Adds the greet_pause rule set, which enables open proxy and SMTP slamming protection. For details, see /etc/mail/cf/README.


The default argument continues to be mail.local, which is the LMTP-capable mailer in this Solaris release. However, in version 8.13, if a different LMTP-capable mailer is used, its path name can be specified as a second parameter and the arguments that are passed to the second parameter can be specified in the third parameter. For example:

FEATURE(`local_lmtp', `/usr/local/bin/lmtp', `lmtp')


Provides experimental support for “Marking Mail Transfer Agents in Reverse DNS with TXT RRs” (MTAMark). For details, see /etc/mail/cf/README.


Works with the access_db rule set to control connection rates for hosts. For details, see /etc/mail/cf/README.


If this FEATURE() is enabled, the rule set check_relay overrides its first argument with this argument, $&{client_ptr}.