There are a couple of these messages that bring up a good point that I'm unsure of: when you use "relay for address," how do you handle clients when you don't know their IP address? That is, is there a way to make "relay for address" work for clients that may come through any arbitrary ISP and have any (unknown) IP address?
Ben Bednarz ----- Original Message ----- From: "John Tolmachoff" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, November 14, 2001 1:42 PM Subject: RE: [IMail Forum] SMTP Relay. What can we do better. Although not the best way, I am currently using Relay for local host only, with Declude Hijack running in back ground. It has solved problems we have had in the past. We are unable to use relay for address because some of our clients are on DSL which uses DHCP. And some of these users are MAC. Unless someone has a better idea. John Tolmachoff, Network Engineer 211 E. Imperial Hwy., Suite 106 Fullerton, CA 92835 714-578-7999, ext. 104 [EMAIL PROTECTED] [EMAIL PROTECTED] www.reliancesoft.com -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of R. Scott Perry Sent: Wednesday, November 14, 2001 10:04 AM To: [EMAIL PROTECTED] Subject: Re: [IMail Forum] SMTP Relay. What can we do better. >Last week, a person was able to relay 300,000 emails through our Imail >server. Our current relay is setup for USERS only. So you were allowing him to send spam. >The person was able to relay mail through our system by changing his computer >name to a domain name in IMail, and creating an email account on his computer >the same as an email account in one of our Imail domains. No, it's not nearly that difficult. In their spamware, when asked "What address do you want listed as the sender of the E-mail", they just entered "[EMAIL PROTECTED]". No changing of computer names, no creating E-mail accounts, no hacking involved. >Since IMail was setup for RELAY FOR USERS ONLY, everything worked correctly. That's correct. "Relay for users" means that you will let anyone relay if they have an account on your server, or are willing to use an E-mail address on your server. >Even if we had setup IMail relay for HOSTS ONLY, the same thing would have >occurred. Quite true. "Relay for hosts" means that anyone can relay mail through your server if they have an account on your server, or are willing to use a made-up E-mail address on your server. > We tried the NO RELAY option, but unfortunately, since the accept.txt > file does not work for NO >RELAY, none of our emails from WhatsUP Gold could be sent, and some of our >third party applications like FrontPage etc... cannot use SMTP >Authentication. With "No Mail Relay", you don't use accept.txt -- it means that everyone has to use SMTP AUTH. "Relay for Addresses" does what you are looking for (although you don't use the accept.txt file, you use the button next to "Relay for Addresses" to list the "safe" IP addresses. >It would be nice if the ACCEPT.TXT file would worked for NO RELAY but it >doesn't. No. "No mail relay" really means "Only relay for people using SMTP AUTH". If IMail let certain users bypass it, then it would be "Relay for Addresses" (which it already has). >I'm a little upset about this because it was pretty simple for this person >to do this ... The problem is that IMail doesn't make it clear that several of their anti-relay options don't prevent spammers from using your mail server. The "Relay for Users" option isn't designed to stop spammers. -Scott --- Declude: Anti-virus, Anti-spam and Anti-hijacking solutions for IMail. http://www.declude.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/ 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/
