We have a novell 5.1 server with groupwise 5.5. We use john.doe@mycompany.com and we are getting alot of spam/virus email to example john@mycompany.com. I'd like to be able to have gwia drop those emails that don't use first.last instead of creating undeliverables that bounce back because the sender is not valid. Is this possible within gwia or is this more a firewall issue? Thanks in advance for any help.
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Need to configure GWIA to reject non users
- Thread starter kklegman
- Start date
MichiganRon
MIS
kklegman,
I don't think this is possible. I'm not sure you'd want to do this anyway. Here's why:
Often spammers will use a dictionary attack to determine which mailboxes are live. Any message which doesn't return a mailer-daemon must be a live mailbox. This puts that address on the spammers list, increasing the amount of traffic to that mailbox. If none of the messages return a mailer-daemon, then expand that out to every email address (valid or not) that they test and the load on your server will increase exponentially.
See where you could run into a problem?
Ron
“If you are irritated by every rub, how will you be polished?”
~ Mevlana Rumi
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I don't think this is possible. I'm not sure you'd want to do this anyway. Here's why:
Often spammers will use a dictionary attack to determine which mailboxes are live. Any message which doesn't return a mailer-daemon must be a live mailbox. This puts that address on the spammers list, increasing the amount of traffic to that mailbox. If none of the messages return a mailer-daemon, then expand that out to every email address (valid or not) that they test and the load on your server will increase exponentially.
See where you could run into a problem?
Ron
“If you are irritated by every rub, how will you be polished?”
~ Mevlana Rumi
Do you live in Michigan? Join us in the Tek-Tips in Michigan forum.
Hi kklegman,
I have my Firewall set up to do the blocking and bouncing of these types of messages. The firewall (instigate) has a built in SMTP gateway (Exim) which is set to forward to my GWIA. Exim does an LDAP lookup for the valid E-mail addresses or checks a list that can be imported and will only pass on real addresses. The firewall sends out the Undeliverable reply and if it is returned by the other mail server catches it. The GroupWise system never has to touch it that way. Every once in a while I purge the dead messages from the firewall.
My firewall is one of the typical Linux appliances so maybe some other brands can do this as well. I think I have heard that some of the AV/SPAM programs also have this feature.
HTH
Ken
I have my Firewall set up to do the blocking and bouncing of these types of messages. The firewall (instigate) has a built in SMTP gateway (Exim) which is set to forward to my GWIA. Exim does an LDAP lookup for the valid E-mail addresses or checks a list that can be imported and will only pass on real addresses. The firewall sends out the Undeliverable reply and if it is returned by the other mail server catches it. The GroupWise system never has to touch it that way. Every once in a while I purge the dead messages from the firewall.
My firewall is one of the typical Linux appliances so maybe some other brands can do this as well. I think I have heard that some of the AV/SPAM programs also have this feature.
HTH
Ken
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