Re: [Declude.JunkMail] Another very effective filter test

[Bill Landry]

John, you should whitelist the IP addresses of you gateways and backup mail exchangers, since you control those systems and because it is very difficult to spoof IP addresses.  That way you will not run into problem with blocking mail from your own systems.   The other this to consider is that if you are using IPBYPASS on you gateways and backup MXs, then you will not have issues either.  Finally, none of your other systems should have the identical host names, so using the IS switch would also prevent FP issues.   Bill ----- Original Message ----- From: John Tolmachoff (Lists) To: [EMAIL PROTECTED] Sent: Thursday, September 25, 2003 12:21 PM Subject: RE: [Declude.JunkMail] Another very effective filter test But then that would cause a problem as I believe Karen had pointed out of when you have a backup MX that sends to the primary.   Then again, 7 is only about 1/3 of my hold weight.   John Tolmachoff MCSE CSSA Engineer/Consultant eServices For You www.eservicesforyou.com   -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Bill Landry Sent: Thursday, September 25, 2003 12:03 PM To: [EMAIL PROTECTED] Subject: Re: [Declude.JunkMail] Another very effective filter test   Matt, what the spammers do is use the names that are listed as you mx records as their helo name, so if your domain is abc.com, but you have your mx records setup as mx1.abc.com and mx2.abc.com, then you will either want to use:   HELO     0    IS    mx1.abc.com HELO     0    IS    mx2.abc.com   or   HELO     0   CONTAINS    abc.com   Bill