nanog mailing list archives
Re: att.net email issues?
From: Sean Donelan <sean () donelan com>
Date: Fri, 24 Jan 2003 19:16:55 -0500 (EST)
Rejecting on broken or non-existing DNS will probably reject mail from more than 15% of all mail servers on the Internet - guaranteeing a false positive rate not even matched by the combined 6 DNSBL's I use - cumulative and with hard 5xx rejects. AT&T on the other hand, will use DNSBL's when the first snowball emerges from hell unscathed.
In the good old days, when network engineers used VT100 terminals and 300 baud (not bps) acoustic modems, ftp.uu.net enforced the requirement for "valid" reverse and forward DNS entries for anonymous FTP access. It was sometimes the only way I could convince customers to type the line in both DNS files. If you don't have valid Address<>Name mappings, you won't be able to download files from ftp.uu.net. Doesn't anyone else find it funny when people scream that ISPs should block ports and shoot people with misconfigured systems; yet when an ISP actually does enforce even a modest requirement; people start screaming how unfair or stupid that ISP is for doing that.
Current thread:
- att.net email issues? Jim Popovitch (Jan 23)
- RE: att.net email issues? Jim Popovitch (Jan 23)
- RE: att.net email issues? Andy Dills (Jan 24)
- Re: att.net email issues? kai (Jan 24)
- Re: att.net email issues? just me (Jan 24)
- Re: att.net email issues? Sean Donelan (Jan 24)
- Re: att.net email issues? Jack Bates (Jan 24)
- Re: att.net email issues? Chris Adams (Jan 24)
- Re[2]: att.net email issues? Richard Welty (Jan 24)
- Re: att.net email issues? kai (Jan 27)
- Re: att.net email issues? just me (Jan 27)
- RE: att.net email issues? Jim Popovitch (Jan 23)
- <Possible follow-ups>
- RE: att.net email issues? Jack McCarthy (Jan 24)