Max sieve string size MTA option

Sieve filter limit MTA options:  (0 &#x3c; integer &#x3c;= 10,000,000)
The  MTA  option specifies the maximum number of characters that may appear in a Sieve string. This includes both string constants, variables, and internally computed string values. The default is 65536; allowed values are integers greater than 0 and less than or equal to 10,000,000.

If a Sieve filter attempts to use more characters in a string than this option allows, Sieve filtering will be aborted (the message being processed will be delivered normally though without Sieve filtering being applied), and the MTA will also generate a notification message to the Sieve owner -- the postmaster for system Sieve filters ( and channel filters), as well as for Sieve filters specified on groups or lists in the aliases file or via alias options, or the user whose Sieve has the error for a user&#x27;s own Sieve filter. The notification message will be constructed using the   file.

Note that prior to the 8.0 release if a Sieve script enables variables, then Sieve Strings are further limited, with hard-coded truncation (with no error message) being performed at 8192 characters. As of 8.0, the  option&#x27;s value is used as intended, even when variables are enabled.

See also:
 * Sieve filter limit MTA options
 * Notification messages