FEATURE(domaintable)

FEATURE(domaintable)

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Rewrite old domain as equivalent to new domain

V8.2 and above

Some sites need to use multiple domain names when transitioning from an old domain to a new one. The domaintable feature enables such transitions to operate smoothly by rewriting the old domain to the new. To begin, create a file of the form:

 old.domain    new.domain 

In it the left side of each line has one of possibly many fully qualified hostnames, and the right side has the new name . The makemap (1) program (Section 5.5) is then used to convert that file into a database.

The domaintable feature causes a rule such as this to be included in your configuration file:

 R $* < @ $+ > $*                 $:  < @ $(domaintable  $) > 

Here, each host part of an address in the canonify rule set 3 is looked up in the domaintable map. If it is found, the new name from that map replaces it.

The domaintable feature enables this lookup by including a K configuration command:

 Kdomaintable hash /etc/mail/domaintable 

The form of the domaintable feature is:

 FEATURE(`domaintable') 

The domaintable feature is one of those that can take an argument to specify a different form of, or different name for, the database:

 FEATURE(`domaintable',`dbm /etc/mail/db/domaintable') 

The extra argument causes the aforementioned K command to be replaced with the following one:

 Kdomaintable dbm /etc/mail/db/domaintable 

You can provide an extra argument that is a literal LDAP:

 FEATURE(`domaintable', `LDAP') 

The default in this instance becomes the following (we have wrapped the lines to fit the page):

 Kdomaintable ldap -1 -v sendmailMTAMapValue -k (&(objectClass=sendmailMTAMapObject) ((sendmailMTACluster=${sendmailMTACluster})(sendmailMTAHost=$j)) (sendmailMTAMapName=domain)(sendmailMTAKey=%0)) 

See ldap (was ldapx) for a description of the ldap database type and its -1 , -v , and -k switches.

Although this feature might appear suitable for a service provider that wishes to accept mail for client domains, it really is not. Such a service provider should use the virtusertable feature (FEATURE(virtusertable)) instead.