Duplicate tracking url MTA option

Sieve duplicate detection:  (memcache URL)
The  MTA option  specifies where duplicate tracking information produced by the Sieve duplicate extension should be stored. At present the value must be a   URL of the form: memcache://host:port/key-prefix If the host isn&#x27;t specified, it defaults to the value of the   MTA option. It is an error for  not to be set in  this case.

If the port isn&#x27;t specified it defaults to the value of the   MTA option; if that option in turn isn&#x27;t specified the default is 11211, the usual port for memcache servers.

, if specified, is prepended to the keys the duplicate extension sends to the memcache server.

See also:
 * Sieve duplicate extension
 * Sieve filter duplicate extension MTA options
 * memcache_host Option
 * memcache_port Option
 * MTA URL types