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sendmail 8.13 Companion by Gregory Neil Shapiro, Claus Assmann, George Jansen, Bryan Costales

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Useful Tables

Two tables are of interest for aiding the suppression of spam:

  • Table 7-1 lists the mc configuration features useful for regulating relaying

  • Table 7-2 lists the righthand-side values useful in the access database

Relay Features

Several mc configuration features affect relaying. Table 7-1 lists the features that determine how mail will, or will not, be relayed.

Table 7-1. Relay features

Feature

sendmail text reference

Description

access_db

7.5[3ed]

Screen addresses and set policy

loose_relay_check

7.4.2[3ed]

Allow percent-hack relaying

promiscuous_relay

7.4.3[3ed]

Allow all relaying

relay_based_on_MX

7.4.4[3ed]

Relay for any site for which you are an MX server

relay_entire_domain

7.4.5[3ed]

Relay based on $=m

relay_hosts_only

7.4.6[3ed]

Interpret domains in relay-domains and access database as hosts

relay_local_from

7.4.7[3ed]

Relay if SMTP MAIL domain is in $=w

relay_mail_from

7.4.8[3ed]

Relay if SMTP MAIL address is RELAY in access database, and provided the entry is properly tagged

Access Database Righthand-Side Values

The access database was introduced in V8.9 sendmail and improved upon in V8.10. It provides a single, central database with rules to accept, reject, and discard messages based on the sender name, address, or IP number. It is enabled with the access_db feature.[11]

In Table 7-2, we list the possible access database righthand-side values (which can be keywords or values) and describe the affect each has ...

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