Import ezmlm-idx 0.40

[ezmlm] / ezmlm-limit.1

.TH ezmlm-limit 1
.SH NAME
ezmlm-limit \- Limits traffic to list
.SH SYNOPSIS
.B ezmlm-limit
[
.B -f\fI file
][
.B -dDF
][
.B \-t
.I secs
][
.B -n
.I msgs
]
.I dir

.B ezmlm-limit
is intended to limit traffic to a list in case an outside
source sends excessive messages. Traffic is limited by converting the list
to a message moderated list, or by deferring messages.

.B ezmlm-limit
reads
.IR dir\fB/loopnum .
If it does not exist or contains a time stamp more than
.I secs
seconds old, it is updated.
If it exists, contains a time stamp less than
.I secs
seconds old, and
.I msgs
messages or more have passed since
.I dir\fB/loopnum
was created,
.B ezmlm-limit
creates
.IR dir\fB/modpost .
For lists set up with
.B ezmlm-store(1)
this results in future messages being moderated.

As long as
.I dir\fB/modpost
does not exist,
.B ezmlm-store(1)
will simply forward the message to
.BR ezmlm-send(1).
Once
.I dir\fB/modpost
exists, messages will be queued for moderation. Thus, in case of error (such
as misconfigured auto responders) subscribers are spared
messages in excess of the limit. However, no messages are lost, since the
moderator(s) can (selectively) approve queued messages. 

If
.I dir\fB/modpost
already exists,
.B ezmlm-limit
will not take any action.

Resetting the list requires manual
removal of
.IR dir\fB/modpost . Queued messages can be managed with regular moderation
or approved in bulk with
.BR ezmlm-accept(1) .

.B ezmlm-limit
is not required for normal lists, since qmail and
ezmlm loop detection prevent problems caused by regular bounces. However,
it affords some protection against malice, and severely misconfigured
subscribers.

.SH OPTIONS
.TP
.B \-d
Defer excess traffic. Excess messages are deferred and qmail will re-deliver. As
a consequence, traffic will be throttled to the maximum allowed. Due to qmail
delivery back-off, messages may not be disseminated in the order received. If
traffic is continuously above or close to the limit, some messages may be
delayed for a long time or even bounced.
.TP
.B \-D
(Default.)
Make the list moderated once excess traffic is detected. This requires the
list to be configured up with
.B ezmlm-store(1)
rather than
.BR ezmlm-send(1) ,
which is easiest done by first creating a message moderated list, then removing
.IR dir\fB/modpost .
.TP
.B \-n\fI msgs
Trigger after
.I msgs
messages (default 30).
.TP
.B \-f\fI file
Instead of
.I dir\fB/loopnum
use
.I file
as the time stamp. This allows the use of multiple instances of
.B ezmlm-limit
for the same list. For instance, you may allow 60 messages per hour with one
instance and 150 messages per day with another. If
.I file
is relative, this is relative to
.IR dir .
.TP
.B \-F
(Default.)
Use
.I dir\fB/loopnum
as the time stamp.
.TP
.B \-t\fI secs
Check the number of messages within period of
.I secs
seconds (default 3600 seconds).
.SH "SEE ALSO"
ezmlm-accept(1),
ezmlm-make(1),
ezmlm-send(1),
ezmlm-store(1),
ezmlm(5)