Hello,
Well, it's Friday and I have little idea as to where to go with this
problem, so I'm sending it to the list for consideration :-)
We have configured exim to handle certain 'special' mailing lists. These
lists can only be posted to by the postmaster(s) as the lists contain all
the staff, all the students, all the Plymouth staff, etc. We don't want
students mailing to them. A message is sent to the list and is picked up by
a director calling a filter which freezes the message. The postmaster checks
the message and unfreezes it. The message then gets picked up by a
subsequent director and goes out to the list. The To: header for a list
looks like 'uop-plymstaff' - they all have the 'uop-' prefix.
This seemed to work fine. However, I have been getting reports that not
everyone on the lists is getting the messages. Checking the logs, I can see
that it is true. The last message sent to Plymouth staff (2200 people)
missed about 700 or so! The messages relate to health and safety, corporate
problems, etc. There were complaints about this one since it affected many
staff at the Uni.
I tested the 'process' by creating a list with just my name in it, and that
worked fine. (I added a bit to the director to prevent the message from being
frozen.) I tried one with a few more names and that worked okay. I used the
exim '-N' option to prevent the messages from being delivered. This too
worked okay. So, I thought go for it and try the Plymouth staff list. Well,
the message went to all the staff! Okay, so it seemed to show that the
special lists was working, but the -N option didn't stop the message from
actually being delivered :-) Hence my embarrasement. Needless to say
my manager wasn't exactly laughing at it!
We are using exim 3.16. The directors are:
special_filter:
no_expn
no_verify
condition = "${if eq {$sender_address} {} {no} {yes}}"
domains = PLYMOUTH (==plymouth.ac.uk)
senders = POSTMASTER (==postmaster@???)
prefix = "uop-"
local_parts = ! uop-replies : *
driver = forwardfile
no_check_local_user
file = TABLES/specials_filter
owners = exim:root
errors_to = POSTMASTER
allow_system_actions
no_ignore_enotdir
no_ignore_eacces
user = exim
filter
special_lists:
no_expn
no_verify
condition = "${if eq {$sender_address} {} {no} {yes}}"
domains = PLYMOUTH
senders = POSTMASTER
prefix = "uop-"
local_parts = ! uop-replies : *
driver = forwardfile
no_check_local_user
headers_remove = "Reply-To:X-Confirm-Reading-To:Return-Receipt-To:X-pmrqc:\
Disposition-Notification-To:X-XFmail-Return-To: \
Resent-From:Resent-To:Resent-Date:Resent-Message-Id: \
Precedence:From"
headers_add = "Reply-To: ${lookup {${lc:$local_part}} lsearch \
{TABLES/lists/special/replies} {$value} {POSTMASTER}}\n\
Precedence: Bulk\n\
From: POSTMASTER"
file = TABLES/lists/special/${lc:$local_part}
forbid_file
forbid_pipe
forbid_include
forbid_filter_logwrite
forbid_filter_reply
one_time
skip_syntax_errors
syntax_errors_to = POSTMASTER
owners = "exim:root"
errors_to = POSTMASTER
(All the headers_remove bit was to prevent 'delivery notifications;
confirmation of reading' etc. It also removes any 'forwarding' headers
(resent-to) etc. The problem was that the wrong reply-to: header was being
picked up if a message was simply 'forwarded' to the list.)
I have put the filters at the end of the message if anyone wants them.
For the problem with the '-N' option the only thing I could think of was
that the message would have been (probably) split up since we use
'remote_max_parallel=8'. Does the '-N' option get passed on to the processes
that are forked by exim? The logs showed that all the messages had '*>'
which the manual says shows that the message is not actually delivered.
For the problem with users being missed from the list I cannot really say.
The situation is not that simple though, since we configure exim to allow
our users to have their mail 'redirected' to a different address (usually
their home ISP) - this could be local or remote. We also allow them to have
'copies' of their mail sent to any other address. In the instance of two
staff here who didn't get the message they both have copies of mail sent to
a remote address. The log does not show their addresses (any of them) at
all. It was simply as if they were not in the list - they are, I checked
that!
The only 'difference' between my sending the message and the postmasters, was
that the postmasters one would have gone through the director which freezes
the message. Perhaps there is some interaction between running a filter
(which uses the first_delivery and freeze options), a subsequent director
using the 'one_time' option and a forwardfile, and then a 'copies' director
using 'unseen' and then another director using an aliasfile. All of which
may have been forked as a seperate process due to the remote_max_parallel
option. Not a simple trail to follow as you can see! (However, it is nice
that exim *can* do all this stuff! :-) ) I should add that all mail passes
through a system_filter as well (!) which does some simple testing of
subject: lines for known viruses. It too uses the 'first_delivery' option
though. Also the act of 'unfreezing' the message is usually done through a
local utility which actually uses 'exim -qqRff plymouth.ac.uk'. Perhaps this
rather than just 'exim -Mt' is causing a problem?
You can see how this is such a problem to try and debug! Sigh.
So, does anyone have any ideas about the '-N' option and/or about forwardfile
missing out people? I thought about going back a version of exim, but 3.16
fixed some other problems for us so I can't really do that. Secondly,
testing this stuff is somewhat difficult since really we need to use a large
list. I shall try and create something which will :blackhole: the mail.
Thanks,
John.
---------------
(Some of the lines have been broken over more than one line)
System filter:
# Exim filter <= Do not edit or remove this line!
if first_delivery then
if $h_Subject: contains "ILOVEYOU" or
$h_Subject: contains "fwd: Joke" or
$h_Subject: CONTAINS "Susitikim shi vakara kavos puodukui" or
$h_Subject: CONTAINS "Mothers Day Order Confirmation" or
$h_Subject: CONTAINS "NewLove-A" or
$h_Subject: IS "Jokes" or
$h_Subject: MATCHES "Funny(\\s+Text)?\\$" or
$h_Subject: MATCHES "Life Stages(\\s+Text)?\\$" then
logfile /usr/local/exim/logs/virus.log
logwrite "$tod_log: $sender_host_address From:
\"$sender_address\" To: \"$h_To:\" Subject:\"$h_Subject:\""
seen finish
endif
endif
finish
-------------------
Special list filter:
# Exim filter <= Do not edit or remove this line!
if first_delivery then
logfile /usr/local/exim/logs/specials.log
if $recipients_count is above 1 then
logwrite "$tod_log: $sender_host_address To: $h_To: Reply-to:
${lookup {$local_part} lsearch
{/usr/local/exim/tables/lists/special/replies} {$value} {postmaster}}
Subject: \"$h_Subject:\""
else
logwrite "$tod_log: $sender_host_address To: ${local_part:$h_To:}
Reply-to: ${lookup {$local_part} lsearch
{/usr/local/exim/tables/lists/special/replies} {$value}{postmaster}}
Subject: \"$h_Subject:\""
endif
freeze text "Special list message"
endif
finish
----------------
------------------------------------------------------------------------
John Horne, University of Plymouth, UK Tel: +44 (0)1752 233914
E-mail: jhorne@???
PGP key available from public key servers
