nanog mailing list archives
Re: Intermittent incorrect DNS resolution?
From: Jay Ashworth <jra () baylink com>
Date: Wed, 16 Jan 2013 19:16:57 -0500 (EST)
----- Original Message -----
From: "Erik Levinson" <erik.levinson () uberflip com>
I'm having an unusual DNS problem and would appreciate feedback. For the zones in question, primary DNS is provided by GoDaddy and secondary DNS by DNS Made Easy. Over a week ago we made changes to several A records (including wildcards on two different zones), all already having a TTL no greater than one hour. The new IPs on those A records have taken many millions of requests since the changes. Occasionally, a small amount of traffic appears at the old IPs that those A records had. This is HTTP traffic. Packet captures of this traffic show various Host headers.
I'm a touch surprised to find that no one has mentioned the facet of Windows OSs that requires "ipconfig /flushdns" in some such circumstances... Not only may *browsers* be caching DNS lookups without regard to TTLs, the *OS* might be doing it to you too, in circumstances I was never quite able to get a handle on. XP was known to do this, as late as SP3; I'm not sure about V or 7. Cheers, -- jra -- Jay R. Ashworth Baylink jra () baylink com Designer The Things I Think RFC 2100 Ashworth & Associates http://baylink.pitas.com 2000 Land Rover DII St Petersburg FL USA #natog +1 727 647 1274
Current thread:
- Re: Intermittent incorrect DNS resolution?, (continued)
- Re: Intermittent incorrect DNS resolution? Erik Levinson (Jan 16)
- Re: Intermittent incorrect DNS resolution? Christopher Morrow (Jan 16)
- Re: Intermittent incorrect DNS resolution? Erik Levinson (Jan 16)
- Re: Intermittent incorrect DNS resolution? Joe Abley (Jan 16)
- Re: Intermittent incorrect DNS resolution? Erik Levinson (Jan 16)
- Re: Intermittent incorrect DNS resolution? Damian Menscher (Jan 17)
- Re: Intermittent incorrect DNS resolution? Erik Levinson (Jan 17)
- Re: Intermittent incorrect DNS resolution? Erik Levinson (Jan 17)
- Re: Intermittent incorrect DNS resolution? Erik Levinson (Jan 16)
- Re: Intermittent incorrect DNS resolution? Robert Bonomi (Jan 16)
- Re: Intermittent incorrect DNS resolution? Vinny Abello (Jan 18)
- RE: Intermittent incorrect DNS resolution? Keith Medcalf (Jan 19)
- Re: Intermittent incorrect DNS resolution? Vinny Abello (Jan 20)
- Re: Intermittent incorrect DNS resolution? Jay Ashworth (Jan 18)
- Re: Intermittent incorrect DNS resolution? Vinny Abello (Jan 18)
- Re: Intermittent incorrect DNS resolution? Andrei Ivanov (Jan 18)