Mike,
You are welcome!
The only choice for not being an open relay, is the 'Relay For Addresses'.
Anything other than that and you will not pass ORBs or other relay tests.
Even if your users have dynamic IPs, you can still use this setting.
However, you users will have to use SMTP Auth (and their clients configured
to support this), if they fall outside the addresses IMail considers local,
to be able to send. Even if using dymanic IP, your addresses probably come
from a particular block and you could tell IMail that whole block of
addresses. This might include some that are assigned to other users of your
ISP, but unless they find your mail server and are spammers, they probably
won't know that they can send email via your server.
I wold suggest that you ask the ISP if he can limit the range of addresses
you get, then you can use that smaller block, instead, with less (or even
no!) chance of others getting those addresses.
One could also use the Web Messaging as the primary method of sending
outside email and that would assure that only your users (with valid
passwords) can send (anyone who connects this way is considered a valid
user). Users could still use POP3 to read mail and send to other local users
(not needing SMTP or other Authentification for IMail to accept mail for
local users).
Since all other domains and their users are not going to be connected to
IMail, either of the above will reduce (nothing is perfect remedy in the
world of spam) your exposure to spammers and their email (at least their
using your server to send the crap).
Note that the above will have no effect on your other domains as they are
local and IMail will still accept email for them and pass it on to the
forward addresses. Users of those domains, would also have to use SMTP Auth,
if they (or you) did decide to use your IMail server for sending to outside
domains.
Daniel Donnelly
________________________________________________________
----- Original Message -----
From: "Mike Franklin" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Tuesday, November 28, 2000 10:31 AM
Subject: [IMail Forum] Mail Relay
> Daniel,
>
> Thanks for your answer yesterday to the control access question. I
re-installed into d:\imail instead of d:\Program Files\imail
>
> Anyway now that I've got it working I'm not sure it was what I wanted
anyway. I'm trying to secure the Imail Server against spam. We
> are a web design company who own our own server and host our customers
domain names. Now we use the Imail server to forward emails
> onto our clients ISP's. We don't allow them to dial up and access our
server. We also use the Imail server for our own email system,
> that is dialing direct into the Imail server to download the company
emails. Each company employee here has their own mailbox. We
> have the SMTP Security set to 'Relay for local hosts only' which seems to
work fine except that one day a while ago, when we were
> inadvertently running an open relay, we were reported and tested by
www.orbs.org who were able to send emails to themselves from our
> Imail server thereby adding us to a blacklist of mail servers.
>
> We then changed the SMTP Security to 'Relay for local hosts only' and
resubmitted our server for testing and they were still able to
> send a couple of test emails to their system from ours.
>
> For the record when we connect to the server we are allocated a dynamic IP
address so it's difficult to block IP address and let
> certain ones through.
>
> We need emails for our clients to get forwarded on and ourselves to be
able to send and receive emails in the office and nothing
> else. Everybody else should be denied access to the server.
>
> Can you enlighten me as to what other changes I need to make to make our
mail server secure.
>
> Thanks in advance
>
> Mike Franklin
> get|e|it
>
>
>
>
> Please visit http://www.ipswitch.com/support/mailing-lists.html
> to be removed from this list.
>
> An Archive of this list is available at:
> http://www.mail-archive.com/imail_forum%40list.ipswitch.com/
>
Please visit http://www.ipswitch.com/support/mailing-lists.html
to be removed from this list.
An Archive of this list is available at:
http://www.mail-archive.com/imail_forum%40list.ipswitch.com/
