Cache debug MTA option

Debug MTA options:  (0 or 1)
The  MTA option controls debugging regarding the  direct LDAP caching of lookup results (domains, aliases, address reversals). The default is, meaning that such debug output is disabled. Setting this option to  enables the debug output; the information is output just before the MTA component exits. (So for instance,    will output information regarding what it cached at the end of its other, normal output---since   most often is used to test just one or a couple of addresses, there is not often much it had to cache. An SMTP server process will output to its log file information regarding what it cached just before it shuts down at the end of its lifetime -- since SMTP server processes typically last for some time, there may be quite a bit of caching that occurred.)

See also:
 * Overview of Direct LDAP configuration
 * Debug MTA options
 * LDAP lookup cache MTA options
 * test -rewrite utility