Chapter 12. Maintain Aliases

Aliasing is the process of replacing one recipient address with one or more different recipient addresses. The replacement address can be that of a single user, a list of recipients, a program, a file, or any mixture of these.

What’s New with V8.13

There is one new aliasing item, but it is not covered until Chapter 23:

  • Extend the default LDAP specifications for the AliasFile option and for file classes to include support for LDAP recursion by way of new attributes (see Section 23.1.2 [V8.13]).

Here, we cover a topic that was only mentioned in a footnote in the third edition.

RFC2142 Common Mailbox Names

The name postmaster is required by RFC2822, and all sites must accept mail to that address.[17] RFC2142 takes the concept of postmaster one step further by recognizing that other roles now correspond to well-known email addresses. For example, most web sites that sell products also accept email to the address sales, which is now a well-known email address.

Table 12-1 shows all the newly required addresses defined by RFC2142. Of these, only postmaster is treated in a case-insensitive manner by sendmail.[18] That is, mail to postmaster, Postmaster, POSTMASTER, and PoStMaStEr will all be delivered to the same person.

Table 12-1. RFC2142-defined email addresses and aliases






Accepts reports of unacceptable behavior



Accepts mail reporting ftp needs or problems


RFC1033 through RFC1035 ...

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