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KEYWORDS= Davrom Consulting Newsletter - Issue # 39 - Dated: 20 Dec 2007


From the desk of David Clark

Seasons Greetings to all of our readers and we would like to take this
opportunity to wish everyone a very Merry Christmas and a Happy New Year.
Almost 2008 - how did we get here so fast? [The traditional ASCII tree as
always has been included]

In this issue I am touching on the power of procmail which can turn your
mail server into a mail-list gateway. I also have touched on getting the
root/admin passwords for customers from anyone who holds or changes them.


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               ##                /o\                  ##
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               ##              /o*/o/\                ##
               ##             /*/\ *\o\               ##
               ##            /\o*\/o\/*\              ##
               ##           /\/*/o\ /*\o\             ##
               ##          /*/\/\ /*o/\/*\            ##
               ##         o    o  #   o   o           ##
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               ##               __#__      __%__      ##
               ##              \_____/    |_____|     ##
               ##                                     ##
               ## /   Merry Christmas From DAVROM   \ ##
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I would like to thank the reader for their time in reading this
newsletter.

David.M.Clark


UNIX Quote

Linux: because a PC is a terrible thing to waste (ksh_at_cis.ufl.edu put
this on Tshirts in '93)


Procmail

Procmail is a powerful email filtering facility that enables users to
manipulate incoming e-mail on a system wide or per user basis. Procmail
facilitates things like automatic replies, forwarding to mail-lists,
saving specific content to other mailboxes/folders and even filtering
spam.

Procmail is a standard package installed on most Linux distributions and
is an add on package for SCO (some issues exist with procmail mailbox
format and SCO's traditional mailbox format). Procmail is a key part of
our EMO product (Electronic Mail Organiser - http://www.davrom.com/emodemo )
and we have been using procmail to service various mail-lists that we
support here at Davrom on our web server. A highly adaptable product, we
have implemented mail-list facilities that allow users in a closed e-mail
group to send and receive e-mail all via the one single e-mail address (eg.,
ourlist@davrom.com) which prevents anyone not in the list from intruding
- goodbye spammers and unwanted e-mails. Controlling the members of the
mail-list group can be done through e-mail itself and can be locked down to
one e-mail address as the administrator of the list.... the options are
unlimited.

Another way to use the procmail mail-lists is to be able to e-mail the one
single e-mail address that then passes the e-mail to those on the list
and can be used as the traditional "no-reply" type sending list.

If you are running IMAP procmail is useful in auto-managing incoming
e-mail into folders based on sender or subject as indicated earlier.

Procmail is often the best method of passing e-mail through anti-virus
and spam filters (eg., ClamAV and SpamAssassin) on a system wide basis.

Yet another nice and powerful facility from the open source community.

Who has your root password?

For years now I have encountered sites where their root password has been
unknown to the owner of the server.

One of my tasks in Linux and UNIX over the years has been to get into a
server and re-set the root password as the suppliers of the original
server had changed it (and in very old sites the suppliers may no longer be
in business), or not divolged it, or the staff at the server owner's
company have moved on and not left the details.

Regardless of the circumstances, you as the customer should always
know the root/administrator passwords for any servers or PCs that
you have - moreover the passwords should never be set or changed without
your express permission granting such changes as the servers/PCs belong
to you.

As a support person I have often seen great delays in getting work done
for customers owing to the need to find out the root password of servers
requiring attention.

There are measures that can be put in place to prevent loss of the root
passwords by configuring features such as "sudo" on Linux and setting
account administrator users up in SCO - this way the root password may
not be required and can be changed if desired through these methods.

Remember, the keys to your car belong to you and in the same light the
most import key to your servers and PCs, the root or administrator
passwords, belong to you.


From the Trenches
Some comic or not so comic relief from the support days gone by.

Just press Select:

Back in the days when dot matrix printers ruled the office I had spent
the best part of a morning talking to a customer about their dot matrix
printer that wasn't printing. As the customer was 1:45 hours drive away and
my day was already full of things I needed to complete, I was eventually
left with the task of driving to see why the printer had stopped and
deferring everything on my slate to the following day.

The printer was relatively new and I had got the customer to check that
it had power, the cables were in the right spot and I even had the customer
re-plug them to make sure. The correct lights were on the front of the
printer and there was paper loaded that responded to the form feed button.

It was a nice coastal drive and I arrived on-site - only to find the
select light, which the customer believed was on, was in fact off. I
pressed the select button and the printer sprang to life with the
multiple queued, and re-queued, jobs.

The customer was quite embarrassed but we turned the visit into a server
health check and all was well.


Tech Tip

Resending an e-mail:

I have often had e-mail that I have received that I wish to re-submit to
the Sendmail e-mail queue. Normally if you just re-send the mail file
itself (eg., /tmp/davrom.eml) you will lose the format, attachments etc.

To resend an e-mail from an already received and saved mail file
use the formail command:

cat /tmp/davrom.eml | formail -s /usr/sbin/sendmail david@davrom.com

- this will resend the e-mail file /tmp/davrom.eml to david@davrom.com
complete as it was originally sent.



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