Mtprioritiesallowed, mtprioritiesrequired Channel Options

Per-channel MT-PRIORITY control
and  are new in the 8.0 release. These channel options enable the MTA&#x27;s support of RFC 6710 (SMTP Extension for Message Transfer Priorities). New in Cayenne, see the   channel option for "tunneling" MT-PRIORITY, via a header field, through systems that do not support the MT-PRIORITY SMTP extension, as described in RFC 6758 (Tunneling of SMTP Message Transfer Priorities).

The  source channel option specifies the range of MT-PRIORITY values that will be accepted. MT-PRIORITY values outside this range will be adjusted up or down so they fall within the allowed range. If a single argument is given, it specifies the highest priority value that will be accepted. The default if this option is not specified is for the MT-PRIORITY extension not to be offered and for MT-PRIORITY parameters not to be accepted.

The  source channel option specifies the range of MT-PRIORITY that will be accepted for enqueue. If a single argument is given, it specifies the lowest priority value that will be accepted. The message will be rejected if the message&#x27;s specified MT-PRIORITY value, or if the default MT-PRIORITY value of 0 (assumed if MT-PRIORITY was not specified in the SMTP transaction), falls outside the required range with the SMTP error: 550 5.7.0 Message priority outside curretly allowed range With either channel option, two integer arguments specify the range. Each argument must be an integer in the range -9..9. The arguments can be given in any order.

See also:
 * include_mtpriority MTA Option
 * log_mtpriority MTA Option
 * Job Controller priority-based processing
 * Processing control and job submission channel options
 * SMTP and LMTP protocol channel options
 * Channel options