database maps for smtpd
Maps provide a generic interface for associating textual key to a value. Such
associations may be accessed through a plaintext file, database, or DNS. The
format of these file types is described below.
itself creates the database maps used by
keyed map lookups specified in
reads input from
and writes data to a file whose name is
made by adding a “.db” suffix to
. The current line can be extended over
multiple lines using a backslash (‘\’). Comments can be put
anywhere in the file using a hash mark (‘#’), and extend to the
end of the current line. Care should be taken when commenting out multi-line
text: the comment is effective until the end of the entire block. In all
reads lines consisting of words
separated by whitespace. The first word of a line is the database key; the
remainder represents the mapped value. The database key and value may
optionally be separated by the colon character.
The options are as follows:
- Specify the format of the database. Available formats are
btree. The default value is
- Write the generated database to
- Specify the format of the resulting map file. The default
map format is suitable for storing simple, unstructured, key-to-value
string associations. However, if the mapped value has special meaning, as
in the case of the virtual domains file, a suitable
type must be provided. The available
output types are:
- The mapped value is a comma-separated list of mail
destinations. This format can be used for building user aliases and
user mappings for virtual domain files.
- There is no mapped value – a map of this type
will only allow for the lookup of keys. This format can be used for
building primary domain maps.
- Instead of generating a database map from text input, dump
the contents of a database map as text with the key and value separated
with a tab.
Primary domains can be kept in tables. To create a primary domain table, add
each primary domain on a single line by itself.
In addition to adding an entry to the primary domain map, one must add a filter
rule that accepts mail for the domain map, for example:
table domains "/etc/mail/domains"
accept for domain <domains> deliver to mbox
Virtual domains may also be kept in tables. To create a virtual domain table,
add each virtual domain on a single line by itself.
Virtual domains expect a mapping of virtual users to real users in order to
determine if a recipient is accepted or not. The mapping format is an
extension to aliases(5)
allows the use of “email@example.com” to accept user only on the
specified domain, “user” to accept the user for any of the virtual
domains, “@domain.tld” to provide a catch-all for the specified
domain and “@” to provide a global catch-all for all domains.
will perform the lookups
in that specific order.
To create single virtual address, add “firstname.lastname@example.org user” to the
users map. To handle all mail destined to any user at example.com, add
“@example.com user” to the virtual map.
In addition to adding an entry to the virtual map, one must add a filter rule
that accepts mail for virtual domains, for example:
table vdomains "/etc/mail/vdomains"
table vusers "/etc/mail/users"
accept for domain <vdomains> virtual <vusers> deliver to mbox
accept for domain example.org virtual <vusers> deliver to mbox
- List of user mail aliases.
- List of remote host credentials.
utility exits 0 on success,
and >0 if an error occurs.
command first appeared in
as a replacement for the equivalent
command shipped with sendmail.