/etc/aliases /etc/aliases.dir /etc/aliases.pag ~/.forward
These files contain mail addresses or aliases, recognized by sendmail.8 for the local host:
In addition, the Network Information Service (NIS) aliases map mail.aliases contains addresses and aliases available for use across the network.
As distributed, sendmail.8 supports the following types of addresses:
username
Each local username is listed in the local host's /etc/passwd file.
pathname
Messages addressed to the absolute pathname of a file are appended to that file.
|command
If the first character of the address is a vertical bar, (|), sendmail.8 pipes the message to the standard input of the command the bar precedes.
username@domain
If domain does not contain any `.' (dots), then it is interpreted as the name of a host in the current domain. Otherwise, the message is passed to a mailhost that determines how to get to the specified domain. Domains are divided into subdomains separated by dots, with the top-level domain on the right. Top-level domains include:
For example, the full address of John Smith could be:
js@jsmachine.Podunk-U.EDU
if he uses the machine named jsmachine at Podunk University.
... [host!]host!username
These are sometimes mistakenly referred to as ``Usenet'' addresses. uucp.1c provides links to numerous sites throughout the world for the remote copying of files.
Other site-specific forms of addressing can be added by customizing
the
sendmail
configuration file. See the
sendmail.8
and
[a manual with the abbreviation ADMIN]
for details. Standard addresses are recommended.
aliasname: address[, address]
aliasname is the name of the alias or alias group, and address is the address of a recipient in the group. Aliases can be nested. That is, an address can be the name of another alias group. Because of the way sendmail performs mapping from upper-case to lower-case, an address that is the name of another alias group must not contain any upper-case letters.
Lines beginning with white space are treated as continuation lines for the preceding alias. Lines beginning with # are comments.
An alias of the form:
owner-aliasname: address
directs error-messages resulting from mail to aliasname to address, instead of back to the person who sent the message.
An alias of the form:
aliasname: :include:pathname
with colons as shown, adds the recipients listed in the file pathname to the aliasname alias. This allows a private list to be maintained separately from the aliases file.
jsmith:js@jsmachine
then any NIS client could just mail to jsmith and not have to remember the machine and username for John Smith. If an NIS alias does not resolve to an address with a specific host, then the name of the NIS domain is used. There should be an alias of the domain name for a host in this case. For example, the alias:
jsmith:root
sends mail on an NIS client to root@podunk-u if the name of the NIS domain is podunk-u.
When an alias (or address) is resolved to the name of a user on the local host, sendmail checks for a .forward file, owned by the intended recipient, in that user's home directory, and with universal read access. This file can contain one or more addresses or aliases as described above, each of which is sent a copy of the user's mail.
Care must be taken to avoid creating addressing loops in the
.forward
file.
When forwarding mail between machines, be sure that the destination
machine does not return the mail to the sender through
the operation of any
NIS
aliases. Otherwise, copies of
the message may ``bounce''.
Usually, the solution is to change the
NIS
alias to direct mail to the proper destination.
A backslash before a username inhibits further aliasing. For instance, to invoke the vacation.1 program, user js creates a .forward file that contains the line:
\js, "|/usr/ucb/vacation js"
so that one copy of the message is sent to the user, and another is piped into the vacation.1 program.
[a manual with the abbreviation ADMIN]
Because of restrictions in dbm.3x a single alias cannot contain more than about 1000 characters. Nested aliases can be used to circumvent this limit.
The Network Information Service (NIS) was formerly known as Sun Yellow Pages (YP). The functionality of the two remains the same; only the name has changed.
Created by unroff & hp-tools. © somebody (See intro for details). All Rights Reserved. Last modified 11/5/97