## Name

courierldapaliasd — LDAP-based mail aliasing

## Synopsis

`courierldapaliasd` {start}

`courierldapaliasd` {stop}

`courierldapaliasd` {restart}

`courierldapaliasd` {query} {`source`} {`address`}

## DESCRIPTION

courierldapaliasd supports mail address aliasing, as implemented by makealiases(8) but using an LDAP directory instead of a GDBM or a DB database. The term "aliasing" refers to substituting one or more addresses for another address. A one-to-one substitution results in the Courier mail server accepting mail for one address, and delivering the mail to another address. A one-to-many substitution results in the Courier mail server accepting mail for one address, and delivering a separate copy of the message to every address defined by the alias.

makealiases(8) uses a GDBM or a DB database to perform the aliasing function. courierldapaliasd uses an LDAP directory instead.

"courierldapaliasd start" runs the courierldapaliasd process in the background, and should be executed at system startup. "courierldapaliasd stop" stops the background process. "courierldapaliasd restart" restarts the process, and rereads the `ldapaliasrc` configuration file to pick up any changes. courierldapaliasd restart must be executed in order for any changes to `ldapaliasrc` to take place.

courierldapaliasd runs in the background and opens a persistent connection to the LDAP directory, and checks every recipient address using the persistent connection. courierldapaliasd automatically starts an adjustable number of multiple processes. With persistent connections being used, this allows alias checking to be as efficient and quick as possible.

"courierldapaliasd query `source` `address`" is a diagnostic tool. It requires that courierldapaliasd must already be running in the background; it sends a query for `address` to the background process, and prints the result. Like makealiases(8) , it is possible to create aliases that are accessible only to certain sources of mail, like "`esmtp`" or "`local`". The "`source`" argument specifies the source of the address, such as "`local`", "`esmtp`", or "`uucp`".

## CONFIGURATION

courierldapaliasd requires OpenLDAP client libraries, and is installed automatically if OpenLDAP client libraries are available at installation time. The default `ldapaliasrc` configuration file contains additional instructions for configuring LDAP-based aliasing.

## FILES

`/usr/sbin/courierldapaliasd`

`/etc/courier/ldapaliasrc`

## SEE ALSO

dot-courier(5) , courier(8) , makealiases(8) , makeuserdb(8) .