Maxmessagerateperdomain smartsend Channel Option

Maximum rate to send to a domain from a single IP
The  smartsend channel option provides the means to limit the rate at which messages are delivered from the channel queue on a per-IP basis. The value of this parameter is one or two space-separated strings of the form n/m, where n is an unsigned integer specifying the number of messages to allow and m is an integer specifying the time window in seconds. If m isn&#x27;t specified it defaults to 3600 (one hour). The first string specifies the rate to use when the IP address is operating normally; the second string specifies the rate to use when operating in IP backoff mode. If the second string is omitted its value defaults to the first string.

Note that the identically named  smartsend  parameter provides the same functionality at the domain or IP level.

This option requires that the smartsend callouts, in particular the callout from the  mapping, be installed. This option will be ignored if smartsend is not configured.

This option also currently requires that a memcache protocol server be configured at either the MTA or channel level.

See also:
 * smartsend callouts