Manual browser: virtual(5)
|VIRTUAL(5)||File Formats Manual||VIRTUAL(5)|
NAMEvirtual - Postfix virtual alias table format
postmap -q "string" /etc/postfix/virtual
postmap -q - /etc/postfix/virtual <inputfile
The optional virtual(5) alias table rewrites recipient addresses for all local, all virtual, and all remote mail destinations. This is unlike the aliases(5) table which is used only for local(8) delivery. Virtual aliasing is recursive, and is implemented by the Postfix cleanup(8) daemon before mail is queued.
- To redirect mail for one address to one or more addresses.
To implement virtual alias domains where all addresses are aliased to addresses in other domains.
Virtual aliasing is applied only to recipient envelope addresses, and does not affect message headers. Use canonical(5) mapping to rewrite header and envelope addresses in general.
The search string is folded to lowercase before database lookup. As of Postfix 2.3, the search string is not case folded with database types such as regexp: or pcre: whose lookup fields can match both upper and lower case.
The input format for the postmap(1) command is as follows:
- pattern address, address, ...
- When pattern matches a mail address, replace it by the corresponding address.
- blank lines and comments
- Empty lines and whitespace-only lines are ignored, as are lines whose first non-whitespace character is a `#'.
- multi-line text
- A logical line starts with non-whitespace text. A line that starts with whitespace continues a logical line.
TABLE SEARCH ORDER
With lookups from indexed files such as DB or DBM, or from networked tables such as NIS, LDAP or SQL, patterns are tried in the order as listed below:
- user@domain address, address, ...
- Redirect mail for user@domain to address. This form has the highest precedence.
- user address, address, ...
Redirect mail for user@site to address when site is equal to $myorigin, when site is listed in $ mydestination, or when it is listed in $inet_interfaces or $ proxy_interfaces.
- @domain address, address, ...
Redirect mail for other users in domain to address. This form has the lowest precedence.
RESULT ADDRESS REWRITING
The lookup result is subject to address rewriting:
- When the result has the form @otherdomain, the result becomes the same user in otherdomain. This works only for the first address in a multi-address lookup result.
- When "append_at_myorigin=yes", append "@$myorigin" to addresses without "@domain".
- When "append_dot_mydomain=yes", append " .$mydomain" to addresses without ".domain".
When a mail address localpart contains the optional recipient delimiter (e.g., user+foo@domain), the lookup order becomes: user+foo@domain, user@domain, user+foo, user, and @domain.
VIRTUAL ALIAS DOMAINS
Besides virtual aliases, the virtual alias table can also be used to implement virtual alias domains. With a virtual alias domain, all recipient addresses are aliased to addresses in other domains.
virtual_alias_maps = hash:/etc/postfix/virtual
virtual-alias.domain anything (right-hand content does not matter)
email@example.com address2, address3
REGULAR EXPRESSION TABLES
This section describes how the table lookups change when the table is given in the form of regular expressions. For a description of regular expression lookup table syntax, see regexp_table(5) or pcre_table(5).
This section describes how the table lookups change when lookups are directed to a TCP-based server. For a description of the TCP client/server lookup protocol, see tcp_table(5). This feature is not available up to and including Postfix version 2.4.
The table format does not understand quoting conventions.
The following main.cf parameters are especially relevant to this topic. See the Postfix main.cf file for syntax details and for default values. Use the " postfix reload" command after a configuration change.
- List of virtual aliasing tables.
- List of virtual alias domains. This uses the same syntax as the mydestination parameter.
- A list of address rewriting or forwarding mechanisms that propagate an address extension from the original address to the result. Specify zero or more of canonical, virtual, alias, forward, include, or generic.
Other parameters of interest:
- The network interface addresses that this system receives mail on. You need to stop and start Postfix when this parameter changes.
- List of domains that this mail system considers local.
- The domain that is appended to any address that does not have a domain.
- Give special treatment to owner-xxx and xxx-request addresses.
- Other interfaces that this machine receives mail on by way of a proxy agent or network address translator.
cleanup(8), canonicalize and enqueue mail
postmap(1), Postfix lookup table manager
postconf(5), configuration parameters
canonical(5), canonical address mapping
Use "postconf readme_directory" or " postconf html_directory" to locate this information.
ADDRESS_REWRITING_README, address rewriting guide
DATABASE_README, Postfix lookup table overview
VIRTUAL_README, domain hosting guide
The Secure Mailer license must be distributed with this software.
IBM T.J. Watson Research
P.O. Box 704
Yorktown Heights, NY 10598, USA