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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical Re: RBL-type BGP service for known rogue networks?
[ On Monday, July 10, 2000 at 09:26:28 (-0400), Shawn McMahon wrote: ] > Subject: Re: RBL-type BGP service for known rogue networks? > > None of which are the case here. Agreed. However I should have listed the other requirement that I thought was self-obvious since we're talking about SMTP here. I.e. I don't ever accept e-mail from anything less than the most strictly conforming SMTP implementations. You're violating part one of RFC 1123 section #5.2.5. The name given by your SMTP server in the HELO "MUST" be a canonical hostname. It must not be a CNAME. To bend the meaning a bit, as Postfix says, "503 polite people say hello first". > The case here is that eiv.com is under my control, but the reverse lookup > for the address is not. No problem. > My hostname is not forged, it's legitimate and it resolves to my proper > IP address via RFC-compliant means. If you lookup oa.eiv.com you'll resolve > the IP unless your DNS is seriously broken. Indeed it does. $ host -t a oa.eiv.com oa.eiv.com CNAME eiv.myip.org eiv.myip.org A 209.26.240.172 Unfortunately as you can see it goes through a CNAME first and that means it's illegal to use in an SMTP HELO greeting (or as an NS target). Why you do this nonsensical mapping in the first place is beyond me. Either do your own dynamic DNS yourself and declare a proper A record and be done with it, or just announce as eiv.myip.org and forget it. The name will only appear in a Received header and it'll usually be accompanied by the name given in the in-addr zone anyway so I really don't understand why you're trying to break SMTP for this reason. > To even suggest that ADSL through the only available provider isn't enough > of a "real" connection for a home user, and that they should instead get > a T1 or something, is beyond ridiculous. Boy do you ever read the wrong things into other peoples words a lot! Since when does "real connection" equal ADSL, T1 or whatever!?!?!?!? I had a *real* connection over 28.8Kbps for several years! A real Internet connection has nothing to do with bandwidth and everything to do with network numbers and routing. My cable modem is much faster but it is not a real Internet connection (even though it does have a static IP#!). The tunnel through it is "real" though.... :-) -- Greg A. Woods +1 416 218-0098 VE3TCP <[email protected]> <robohack!woods> Planix, Inc. <[email protected]>; Secrets of the Weird <[email protected]>
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