http://www.spambouncer.org
I have no connection to this software other than being a satisfied user. -Paul At 07:29 PM 2/28/2002, Nicole Harrington wrote: > Hi > Does anyone know of a program that can flag such things and alter mail > headers >on the fly like this? > > > Nicole > > >On 28-Feb-02 Unnamed Administration sources reported Jared Mauch said : > > > > On Thu, Feb 28, 2002 at 01:35:09PM -0700, Daniel Lark wrote: > >> > >> You are most correct, it is definitely a double edged sword. Let's say > >> you try to reverse DNS on an address who's nameserver is down or > >> otherwise unreachable, what then? Some admins I know deliberately do run > >> reverse DNS as they view it as system cracker tool, or they feel it is > >> an unwarranted load, RFCs be damned. Is this admin decision the fault of > >> the user? > > > > Use a non clueless isp. the market is fairly saturated in > > most places with service providers. > > > >> You are not first one to try this. I have tried this myself and a > >> financial type didn't get an important email because of it. You know the > >> rest of the story. > > > > What I do is format my smtp headers such that a very simple > > regex can find mail with no reverse dns and dump it in a spam folder. > > I find this catches a lot of the messages. > > > > I try and let people know but for example, I am unable to > > find anyone at American Express or NWA that can fix their dns. > > (others are prompt in fixing their dns problems). > > > >> A better solution is to check the ip and see if it is an MX record for > >> the domain the mail purports to be from. > > > > This has a number of flaws. I won't delve into them though. > > > >> Just my opinion, and I could wrong. > > > > - Jared > > > >> > >> -dan > >> > >> -----Original Message----- > >> From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of > >> Patrick Muldoon > >> Sent: Thursday, February 28, 2002 1:15 PM > >> To: [EMAIL PROTECTED] > >> Subject: Reverse DNS and SMTP > >> > >> > >> We have recently implemented a policy on our mail servers of not > >> accepting mail from hosts that do not correctly resolve via reverse DNS. > >> While we on the technical side love the idea, there have been some > >> questions from the business side of the house. > >> > >> If an ISP who doesn't have reverse DNS setup correctly on their > >> mail servers, we point them to the RFC's and generally offer to help > >> them correct it. > >> We have noticed that our spam has reduced drastically, and the > >> complaints are few, but alas this is a double edged sword, where if you > >> even block 1 legitimate e-mail out of the 100K+ that we receive daily, > >> someone is going to complain. > >> > >> Just curious if anybody here is doing the same and the response that > >> they have had from doing so. Replies off list are fine and I will > >> summarize if people are interested. > >> > >> Thanks, > >> Patrick > >> > >> -- > >> Patrick Muldoon, Network/Software Engineer > >> INOC, LLC > >> [EMAIL PROTECTED] > >> > >> Press Ctrl-Alt-Del now for IQ test. > >> > >> > > > > -- > > Jared Mauch | pgp key available via finger from [EMAIL PROTECTED] > > clue++; | http://puck.nether.net/~jared/ My statements are only mine. > > > > |\ __ /| (`\ > | o_o |__ ) ) > // \\ > Daemon Technologies(tm) | Phone: 510.895.9667 > [EMAIL PROTECTED] | >-------------------(((---(((----------------------- > - Powered by FreeBSD - > Email, DNS, SiteHosting, FTP Services, > Dedicated Servers, Co-Location, and a Lot More >------------------------------------------------------ > " Daemons" will now be known as "spiritual guides" >-Politically Correct UNIX Page