DeskLink Newsletter Volume #2

Welcome DeskLink Customers

This is the second e-mail newsletter sent to our DeskLink customers; it is intended to let those of you with support contracts know about new and planned features of DeskLink, along with a few tips on ways you can use the system you have which you may not be aware of. We will try to make this a regular feature (one issue every 1-2 months), while also trying not to take too much of your valuable time by sending too many issues.

Those of you with Internet e-mail addresses should receive this by e-mail, others will receive it via fax. If you get a fax but have an Internet e-mail address you would prefer us to use, please let us know. Those of you who do not want to receive any more notices (these are intended to highlight features you have already paid for; not merely plugs for additional products) may let us know and we will remove you from the distribution list. Note that we will also use this list to make you aware of important problems or bug reports if applicable, so I urge you to have someone at your site at least review these messages. Also - anyone who would like us to add other mailboxes to our distribution (others at your site that might be interested) you may also let us know.

Finally, if you have questions about DeskLink or any other 3k Associates product (NetMail/3000, PopServer, Gopher Server, Ftp Server, Fax Server) feel free to give us a call at +44 1480 492400 or e-mail us at sales@3kassociates.com or support@3kassociates.com.

Now that we're done with that...

In this issue:
 1) Tracking down undeliverable mail
 2) Controlling inbound mail-headers that appear in HPDesk
 3) Preventing your server from being used to "relay" spam
 4) New feature preserves PC file attachment names
 5) Using the POP Server with DeskLink
 6) Redirecting incoming mail (using the ALIASES.DATA.THREEK file)
 7) Tell a friend - make a difference!
 8) Just for fun
**If you don't read anything else, PLEASE read the section on preventing
  your system from being used to relay spam. We (in tech support) get a
  disturbing number of calls from sites after they have been victimized;
  it's so easy to prevent - and so costly to clean up - that if your
  system is accessible from the Internet, you *NEED* to know about this.
  Your BUSINESS may depend on it!
  Don't assume that 'they' won't find you; automated programs in use all
  over the Internet scan for any mail server that has Internet access and
  record them for later (ab)use. Professional spammers are even exchanging
  these lists, so if you get hit once, you're very likely to be hit again
  if you don't do something about it. It can happen to anyone; we have
  caught two attempts at relaying through our servers in the past two
  months. (Happily, both were entirely unproductive for the spammers and
  we were able to catch both spammers while they were still online!)

Tracking down undeliverable mail - Part 1

  On occasion, you may be faced with the task of tracking down a message
that "didn't arrive" at it's destination. Doing this often takes a bit
of "net detective" work, but like any good mystery, there are usually
clues available to those that know where to look.
  The detective work required increases with every "hop" (or system) that
a message must pass through, but most systems do have facilities (though
they're not always enabled) to track down messages that have passed through
the mail system. Each mail system has various "queues" of mail, usually
grouped by it's destination system. Sometimes network connections "break"
and queues get "stuck". Sometimes administrators make unfortunate changes
to mail system configurations and various problems manifest themselves.
  Probably a good first step is to try and get a general idea of which system
has a "problem". For instance, user "A" on your system complains that he
can't get a message to user "B" on system2. Some initial things to check:
 * Can anyone else send a message to "B" on system2? Has this person
   gotten any other mail from outside systems?
 * Can user "A" send mail to anyone else on OTHER systems? Anyone else on
   the same (system2) system?
 * Can anyone on your system get a message to "B" on system2?
Some places to look for "clues" on your system:
 * First - check the outbound mail queues in NetMaint. Is the outbound
   message still sitting in the queue? If so, then there's a problem
   connecting to the remote system -- or you forgot to start your background
   netmail job! Ping the remote system. Try telnet'ing to the remote system's
   mail port (port 25). To do this:
    :RUN TELNET.SYS.THREEK
    telnet>OPEN system2 25
   In response to this, you should get a response starting with "220". If
   so, then that system *is* reachable and it's mailer is running. Type
   "quit" to end the telnet program.
 * Check the SMTPOULG.NETMAIL file for a record of the message in question
   having left the system. If you see evidence of the message there (it's
   subject/from/to) then the message DID leave this system. Messages aren't
   logged until the message has left the system. [If you haven't built the
   SMTPOULG -and other log files- sign on under the account which the
   netmail/desklink job runs (threek or hpoffice) and issue the following:
    :build smtpoulg.netmail;rec=-512,,v,ascii;disc=100000,32;cir
    :build smtpinlg.netmail;rec=-512,,v,ascii;disc=100000,32;cir
    :build deskoulg.netmail;rec=-512,,v,ascii;disc=100000,32;cir
    :build deskinlg.netmail;rec=-512,,v,ascii;disc=100000,32;cir
    :build errorlog.netmail;rec=-256,,f,ascii;disc=10000;cir

Controlling inbound mail-headers that appear in HPDesk

  The headers that appear in the "body" of your messages in HPDesk are
configurable in DeskLink.
  Since HPDesk's FSC interface (the interface used by 'gateways' like DeskLink
to import messages from and export messages to HPDesk) does not allow us to
pass a 'full' distribution list into HPDesk for messages coming from foreign
systems, we added a feature in DeskLink which optionally copies some of the
actual Internet headers (like full To:, Cc: and some other headers) into the
body of the message imported into HPDesk. This way, users reading messages
coming in from the 'outside' can see the full distribution lists on their
messages without having to open and examine the 'arpa headers' part of the
message (which can be quite long and full of other irrelevant headers).
  By default, if you turn this feature on (which is designated in the
Netmaint program in the HPDesk configuration screen) you will see the
following headers (if they are present in the original message that is):
  FROM
  TO
  SENDER
  CC
  RESENT-FROM
  RESENT-TO
  RESENT-SENDER
  RESENT-CC
  RESENT-DATE
  You can fine-tune this list if you desire. Headers are listed in the file
'DESKHEAD.DATA.THREEK'. You can add to the list (one header per line, in any
order) or remove entries if you like.
  Note that since Internet messages can have a separate 'From', 'Reply-to',
'Sender' and potentially 'Resent-' versions (if a message was forwarded) and
HPDesk only understands the concept of a single return (from) address, seeing
the from/sender/resent-from/resent-sender fields can potentially provide
useful information to a recipient about a message's origin.

Preventing your server from being used to "relay" spam

  Mail servers all over the world are being victimized on a daily basis by
shady "spammers" using any "open" mail server they can access to send their
bounty of trash messages. They submit, often tens or hundreds of thousands
of trash messages, through their victim's servers, usually with forged
return addresses, then disappear to let the victim handle the thousands upon
thousands of undeliverable messages, and the barrage of complaints and
often mailbombing or other attacks from unwilling spam recipients.
  Anyone who has been through this can attest that is a maddening,
humbling, and very expensive attack to recover from.
  To defeat these criminals, you need to understand how they work. Using
mail clients specifically designed to hide their identity, they find a mail
server which will "relay" messages for them. Relaying means that they can
submit a massive quantity of messages in a single (or multiple simultaneous)
streams very quickly to a server; normally the process of delivering mail
messages is a slower, time-consuming process as there are many DNS lookups
required and connections must be made to multiple mail systems around the
world. By handing off all this work to someone else's machine, the spammer
can unload a massive amount of messages in a short time; then disappear back
into the shadows.
  Some of the trademarks of these attacks are that these mailers, by
necessity, transmit a long list of recipients to the mail server, followed
by one message body. Basically sending the exact message to hundreds or
thousands of addresses.
  A new feature in DeskLink as of version B.06 is enabled via a job
control word (JCW) in the desklink job. This jcw, MAXSMTPRCPTS is
set to 0 (zero) by default; but can be set to any number >0 and <32000.
This setting allows you to catch users submitting massive amounts of
mail messages to your server from an outside source. By setting this jcw
to 100 (for example), any attempt to submit the same message to more than
100 recipients (this is COMING from another system) will be prevented.
Obviously, if you have more than 100 persons on your system and are likely
to get messages (say mailing lists) that do regularly get sent to more than
100 of your users, then you'll need to adjust this threshold appropriately.
  When someone attempts to relay messages through your system AND exceeds the
MAXSMTPRCPTS limit you set, their message will be dropped, their connection
(between your server and the server submitting the messages) will be term-
inated, and error messages will be logged to the system console and to
the "ERRORLOG" file indicating the problem and where the "spammer" is coming
from (his IP address and hostname -if available).
  In the event of a spam-relay attack, it is important that you determine the
Internet provider that the spammer is using (if you need help with this, let
us know) and notify them immediately. Some ISPs log their dial-in users but
only keep the logs for a limited time. Keep copies of the messages from your
errorlog file in case you need evidence if you choose to pursue legal actions
against the attacker.

New feature preserves PC file attachment names

  A new enhancement, made in cooperation with engineers at Hewlett Packard
allows for message attachments to retain their original filenames when
passing into or out of HPDesk.
  For OpenDesk clients, this simply means that when you receive a message from
an external user, you will see their original filename on the attachment(s).
Likewise, on messages you send, your recipients will see the filename(s) you
used, which helps identify what the attachment really is.
  For HPDesk (terminal) user-interface users, if you want to attach a file
and pass a filename on with the attachment (like "myfile.xls") you need to
do two things;
 1) make sure the file you're attaching has an appropriate filecode -
    according to the "pcfiles.data.threek" file which has a master list of
    pc filetypes to MPE filecodes
 2) when you attach the file in Desk, when prompted for a "subject" for that
    attachment, enter the filename.extension that you want the recipient to
    see (i.e. "myfile.xls" -- the filename part can be between one and eight
    characters long and the extension should match the filetype and be between
    one and three characters long).
To get this to work, you need a few pieces of software:
 1) You'll need DeskLink version B.06 with a datecode of October 20 or later.
 2) You'll need the following patches from HP for OpenDesk:
   - OD3017 which preserves filenames on attachments leaving HPDesk
   - OD3016 which captures filenames on attachments coming into HPDesk
  By the way; a new filetype just added to our control file - 9979 - allows
you to attach a "text" file, yet still designates it as an "attachment"
instead of an "inline" message part as all text attachments were previously
designated. You need the updated PCFILES file and a DeskLink release B.06
from October 1997 (or later).

Using the POP Server with DeskLink

  Many of our DeskLink customers are already familiar with other mail systems.
Common uses of DeskLink include integration and communications with other
corporate mail systems, including the likes of Microsoft Exchange and (IBM)
Lotus Notes.
  Some sites have also embraced HP's 'GUI' clients for e-mail access to HP
OpenDeskmanager from PC clients. Such graphical clients bring ease-of-use
and the economy of mass-market e-mail clients to the HP3000 shop. The
benefits of the HP3000 as a mail server (as in any mission critical role)
are well known to long time HP3000 users and administrators -- the machines
take little administration, run reliably, perform well, and scale from
small 8-user systems to mainframe class systems with thousands of users and
terabytes of storage.
  With the advent of popular, reliable, and very functional 'POP' (Post Office
Protocol) e-mail clients brought about by the Internet, HP3000 shops have
another choice in e-mail clients for their users. By adding a POP Server to
your 3000 you can provide e-mail access to your clients using packages like
Qualcomm's Eudora (freeware and commercial versions), Pegasus (freeware),
Netscape, or Microsoft's Exchange or Outlook clients. They get their choice
of (free or very low cost) mail clients; you get the peace of mind of the
HP3000 as your mail server, and an easy upgrade for DeskLink users. Using
the same background job you already run for DeskLink (additional servers are
launched automatically by this job) and the same maintenance program you use
with DeskLink (Netmaint.pub.threek) you can easily add 'POP' accessible
mailboxes to your existing mail system. [Note; these mailboxes are NOT HPDesk
mailboxes- they use DeskLink's mail database and files, though POP mailboxes
can easily exchange mail with HPDesk users as well as any remote or Internet
mail systems your DeskLink system can access.]
  For a free demo of the Pop Server you can enable on your DeskLink system,
contact our sales office.

Redirecting incoming mail (using the ALIASES.DATA.THREEK file)

  Borrowing from the Unix world, the concept of a simple means of redirecting
incoming e-mail from one address to another inspired the addition of an
'aliases' file supported by DeskLink (and all our other e-mail products).
  A simple ascii file which you can create yourself with any editor (just
be SURE to keep it UNNUMBERED) you merely enter the incoming address
followed by a ":" followed by the address you want the message redirected
to. For example:
user1@myhost.acme.com:postmaster@hp.com
  Important restrictions; the address on the left side of the ":" must
EXACTLY match the incoming address. Also, there can only be one address on
the right side of the ":". (To redirect messages to more than one address,
use a mailing list in the Netmaint program). The address you redirect to
can be a local address (HPDesk or POP mailbox for example) or a remote
mailbox (on some other system). Also, these aliases are ONLY parsed on
messages coming into the system via SMTP -- they will NOT work for messages
leaving HPDesk and passing out through the gateway for instance.
  You can specify as many redirections as you like in the aliases file, one
per line (record).

Tell a friend - Make a difference!

  Thru January 31, 1998, helping a colleague mail-enable their HP 3000
system can help your company - or a certified charity of your choosing.
  If you know of an HP 3000 site that could benefit from mail-enabling their
HP3000 users or applications, then give us a call. Through January 31, 1998,
any such referrals that lead to a purchase of NetMail/3000 (unlimited
mailbox version) or DeskLink will net the referrer a choice of:
* One free year added to their organization's technical/update support
  contract for any one of our products
-or-
* A $250 contribution made in their name to the certified charity of their
  choice (or if you choose, we'll send your contribution to our favorite
  charitable organization; the Bethany House of Northern Virginia, which
  does wonderful work providing shelter and assistance to battered and abused
  children and spouses.)
  Charitable contribution options are also available for all other 3k
Associates e-mail products. Offer valid only in North and South America.
Contact our sales office for details at (800) Net-Mail or +1 703 569-9189.

Just for fun

  Many of you may not be aware that among other things, built in with every
NetMail/3000, DeskLink, or Popserver/3000 package is a little Internet service
called "quote of the day". It's exactly what it sounds like; every time it's
called, it returns a cute "quote".
  While not earth shattering, it can come in useful. For example, the job
stream below, scheduled say once a day, will append a "quote of the day" to
your systems welcome message!
  The job assumes that you keep the standard text for your welcome message in
a file called "welcome.pub.sys" (change the file reference if needed). You'll
also need to change the info= string to reflect the name of YOUR hp3000 (or
one of your HP3000s that runs the netmail or desklink job).
!job newwelc,manager.sys
!comment this user will need to be allowed the "WELCOME" command
!comment -you may need to run an "allow" program (available from the CSL
!comment  and other places)
!comment
!continue
!purge welc2
!build welc2;rec=-80,,f,ascii;disc=100
!file w2=welc2,old;acc=append
!fcopy from=welcome.pub;to=*w2
!build tempw;rec=-80,,f,ascii
!file app=tempw,old;acc=append
!comment
!comment be sure to change the 'myhost.mydomain.com' to the name of your
!comment system
!comment
!run get.sys.threek,quote;info="myhost.mydomain.com";stdlist=*app
!listf tempw,2
!print tempw
!echo Quote for the day: > *w2
!fcopy from=tempw;to=*w2;subset=2
!echo > *w2
!print welc2
!continue
!purge tempw
!continue
!welcome welc2
!continue
!purge welc2
!set stdlist=delete
!eoj

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