Chapter 11. Manage the Queue

Mail messages can be either delivered immediately or held for later delivery. Held messages are referred to as queued. They are placed into either a single holding directory (usually called mqueue) or several directories from which they are later delivered.

What’s New with V8.13

  • The qf file’s V line has been bumped to V8 in support of queue quarantining (Section 11.1.1 [V8.13]).

  • Queue quarantining is now officially supported (Section 11.1.2 [V8.13]).

  • The qf file’s new q line lists the quarantine reason (Section 11.1.5 [V8.13]).

  • You may now manage lost (Qf file) envelopes (Section 11.1.6 [V8.13]).

  • Tunable queue-processing delays (Section 11.1.4 [V8.13]).

  • The new confTO_QUEUERETURN_DSN mc macro (see Section 4.1.3 [V8.13]).

  • The new confTO_QUEUEWARN_DSN mc macro (see Section 4.1.4 [V8.13]).

The qf File’s V Line

The V line (11.11.19[3ed]) in the qf file (11.2.5[3ed]) corresponds to the version of sendmail that created it. Table 11-1 compares V line qf file versions to corresponding sendmail versions.

Table 11-1. Queue qf file versions

V version

sendmail version


8.6 and earlier


8.7 and 8.8




8.10 and 8.11 built with -D_FFR_QUEUEDELAY not defined


8.10 and 8.11 built with -D_FFR_QUEUEDELAY defined


8.12 built with -D_FFR_QUEUEDELAY not defined


8.12 built with -D_FFR_QUEUEDELAY defined



Note that the qf file’s V8 line corresponds to V8.13 sendmail, which added official support for queue quarantining.

Queue Quarantining ...

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