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| Subject: | Re: educating rDNS violators |
|---|---|
| Date: | Wed, 25 Aug 2004 07:00:35 -0400 |
On Mon, 2004-08-23 at 15:24, JGrimshaw@ASAP.com wrote:
I was under the impression that reverse DNS for the Internet was essentially broken, due to several large ISPs not necessarily implementing reverse DNS for their many subnetted customers.
I have the (mis)fortune of being a customer of a large ISP who resells a portion of a class C to us. As with most customers in this situation I run my own DNS with no authority over my reverse DNS. But if you call your ISP's help line and ask them to correct your reverse DNS entry for your mail servers they more than likely will be ecstatic to help you out. Personally, I can say my spam reduced over 85% by dropping mail that doesn't come from a server with correct reverse DNS information. All ISP's want to see spam reduced and if your ISP won't assist you in correcting your reverse info, I'd be shopping for a new ISP. Hope this helps someone out! -- Derek Schaible <dschaible@cssiinc.com> CSSI, Inc.
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