nanog mailing list archives
Re: what happens when you put a typo in a DNSBL server?
From: Steve Atkins <steve () blighty com>
Date: Wed, 17 Jan 2007 08:33:20 -0800
On Jan 16, 2007, at 8:36 AM, Wes Hardaker wrote:
A number of ISPs use njabl.org as a DNS BL server. However, starting jan 2 a new domain exists "njalb.org" which is serving A records for anything queried against it's DNS server. (note the difference: njaBL vs njaLB). Previous to this date a misconfigured ISP was just not being protected by the BL. Now, it's potentially dropping all mail from anyone because of the typo.
If you screw up your mail configuration, you'll lose email. I'm more concerned about the deluge of DNS queries caused by people who randomly punch strings into their mailfilters and cause quite a lot of traffic to third party DNS servers. When I see people doing that to my DNS servers, I add a wildcard record in the hope that they'll notice. The worst case is when they're hitting the (non-existent) blacklist just to get a value to feed into something like spamassassin that will proceed to deliver the mail anyway. There are de-facto standards that will prevent all this happening, but the writers of spam filters are (as far as I know, without exception) too stupid or too lazy to take advantage of this. Cheers, Steve
Current thread:
- what happens when you put a typo in a DNSBL server? Wes Hardaker (Jan 16)
- Re: what happens when you put a typo in a DNSBL server? Alexander Harrowell (Jan 16)
- Re: what happens when you put a typo in a DNSBL server? John Levine (Jan 16)
- Re: what happens when you put a typo in a DNSBL server? Wes Hardaker (Jan 16)
- Re: what happens when you put a typo in a DNSBL server? John L (Jan 16)
- Re: what happens when you put a typo in a DNSBL server? Steve Sobol (Jan 19)
- Re: what happens when you put a typo in a DNSBL server? Wes Hardaker (Jan 16)
- Re: what happens when you put a typo in a DNSBL server? Chris L. Morrow (Jan 16)
- Re: what happens when you put a typo in a DNSBL server? Steve Linford (Jan 16)
- Re: what happens when you put a typo in a DNSBL server? Steve Atkins (Jan 17)