File Formats aliases(4)
NAME
aliases, addresses, forward - addresses and aliases for
sendmailSYNOPSIS
/etc/mail/aliases
/etc/mail/aliases.db
/etc/mail/aliases.dir
/etc/mail/aliases.pag
~/.forwardDESCRIPTION
These files contain mail addresses or aliases, recognized by
sendmail(1M) for the local host: /etc/passwd Mail addresses (usernames) of local users./etc/mail/aliases
Aliases for the local host, in ASCII format. Root can edit this file to add, update, or delete local mailaliases.
/etc/mail/aliases.{dir , pag}
The aliasing information from /etc/mail/aliases, in
binary ndbm(3C) format for use by sendmail(1M). The pro-
gram newaliases(1M) maintains these files.
/etc/mail/aliases.db
The aliasing information from /etc/mail/aliases, in
binary, Berkeley DataBase format for use by sendmail(1M). The program maintains these files. Depending on the configuration of the AliasFile option in /etc/mail/sendmail.cf, either the single filealiases.db or the pair of files aliases.{dir, pag} is
SunOS 5.11 Last change: 10 Dec 2009 1
File Formats aliases(4)
generated by newaliases(1M). As shipped with Solaris,
sendmail(1M) supports both formats. If neither is speci-
fied, the Berkeley DataBase format which generates the single .db file is used. ~/.forward Addresses to which a user's mail is forwarded (see Automatic Forwarding).In addition, the NIS name services aliases map mail.aliases
contains addresses and aliases available for use across the
network. Addresses As distributed, sendmail(1M) supports the following types of addresses: Local Usernames username Each local username is listed in the local host's /etc/passwd file. Local Filenames pathname Messages addressed to the absolute pathname of a file are appended to that file. Commands |command If the first character of the address is a vertical bar (|), sendmail(1M) pipes the message to the standard input of the command the bar precedes.Internet-standard Addresses
username@domainSunOS 5.11 Last change: 10 Dec 2009 2
File Formats aliases(4)
If domain does not contain any `.' (dots), then it is inter-
preted as the name of a host in the current domain. Other-
wise, the message is passed to a mailhost that determines how to get to the specified domain. Domains are divided intosubdomains separated by dots, with the top-level domain on
the right. 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. uucp Addresses ... [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 cus-
tomizing the sendmail.cf configuration file. Seesendmail(1M) for details. Standard addresses are recom-
mended. Aliases Local Aliases/etc/mail/aliases is formatted as a series of lines of the
form 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 ofanother alias group. Because of the way sendmail(1M) per-
forms mapping from upper-case to lower-case, an address that
is the name of another alias group must not contain anyupper-case letters.
Lines beginning with white space are treated as continuationlines for the preceding alias. Lines beginning with # are
comments.SunOS 5.11 Last change: 10 Dec 2009 3
File Formats aliases(4)
Special Aliases An alias of the form:owner-aliasname : address
sendmail directs error-messages resulting from mail to
aliasname to address, instead of back to the person who sent the message. sendmail rewrites the SMTP envelope sender tomatch this, so owner-aliasname should always point to
alias-request, and alias-request should point to the owner's
actual address:owner-aliasname: aliasname-request
aliasname-request address
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 listto be maintained separately from the aliases file.
NIS Domain AliasesThe aliases file on the master NIS server is used for the
mail.aliases NIS map, which can be made available to every
NIS client. Thus, the /etc/mail/aliases* files on the vari-
ous hosts in a network will one day be obsolete. Domain-wide
aliases should ultimately be resolved into usernames on
specific hosts. For example, if the following were in thedomain-wide alias 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.SunOS 5.11 Last change: 10 Dec 2009 4
File Formats aliases(4)
For example, the alias: jsmith:rootsends mail on an NIS client to root@podunk-u if the name of
the NIS domain is podunk-u.
Automatic Forwarding When an alias (or address) is resolved to the name of a user on the local host, sendmail(1M) checks for a ~/.forward file, owned by the intended recipient, in that user's home directory, and with universal read access. This file cancontain 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 mailto the sender through the operation of any NIS aliases. Oth-
erwise, 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 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 program. The ~/.forward file can be used to specify special "per user" extensions by creating a .forward+extension file in the home directory. For example, with an address like jsmith+jerry@jsmachine, the sendmail(1M) utility recognizes everything before the "+" as the actual username (jsmith)and everything after it, up to the "@" symbol, as the exten-
sion (jerry) which is passed to the mail delivery agent for local use. The default value of the ForwardPath processing option in sendmail(1M) is:SunOS 5.11 Last change: 10 Dec 2009 5
File Formats aliases(4)
O ForwardPath=$z/.forward.$w+$h:$z/.forward+$h:$z/.forward.$w:$z \
/.forwardwhere $z is the macro for the user's home directory, $w is
the macro for the local machine name and $h is the exten-
sion. For example, for mail using the address, jsmith+jerry@jsmachine, the sendmail(1M) utility checks each of the four following file names, in the order given, to see if it exists and if it has "safe" permissions, that is, that neither the file nor any of its parent directories aregroup- or world-writable:
~jsmith/.forward.jsmachine+jerry ~jsmith/.forward+jerry ~jsmith/.forward.jsmachine ~jsmith/.forward The first file that meets the conditions is used to forward the mail, that is, all the entries in that file receive a copy of the mail. The search is then stopped. FILES /etc/passwd Password file /etc/nsswitch.conf Name service switch configuration file/etc/mail/aliases Mail aliases file (ascii)
/etc/mail/aliases.db Database of mail aliases (binary)
/etc/mail/aliases.dir Database of mail aliases (binary)
/etc/mail/aliases.pag Database of mail aliases (binary)
/etc/mail/sendmail.cf sendmail configuration file ~/.forward Forwarding information fileSunOS 5.11 Last change: 10 Dec 2009 6
File Formats aliases(4)
ATTRIBUTES
See attributes(5) for descriptions of the following attri-
butes:_____________________________________________________________
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
|_____________________________|______________________________|
| Availability | service/network/smtp/sendmail||_____________________________|______________________________|
SEE ALSO
passwd(1), uucp(1C), vacation(1), newaliases(1M),
sendmail(1M), ndbm(3C), getusershell(3C), passwd(4), shells(4), attributes(5) NOTES Because of restrictions in ndbm(3C), a single alias cannot contain more than about 1000 characters (if this format is used). The Berkeley DataBase format does not have any suchrestriction. Nested aliases can be used to circumvent this
limit.For aliases which result in piping to a program or con-
catenating a file, the shell of the controlling user must be allowed. Which shells are and are not allowed are determined by getusershell(3C).SunOS 5.11 Last change: 10 Dec 2009 7