nanog mailing list archives
RE: DNS DOS increasing?
From: James Smith <jsmith () PRESIDIO com>
Date: Mon, 21 Jan 2002 10:07:32 -0500
I've seen DOS-type behavior where a client will query a resolver for a name that doesn't exist, and the client does not accept the answer that the name does not exist and immediately sends another query, regardless of whether or not the resolver declared itself authoritative for the negative answer. -- /ak Get ready for more DOS-like behavior as systems get deployed that have 10 second TTLs in the DNS. These systems are used to provide multi-isp redundancy by pinging each upstreams router, and when a ping fails, start giving out a dns response using the other ISP IP range. Same FQDN, new IP. This of course is driven by the desire for redundancy in small businesses who make the Internet an integral part of their business plan. Either they can't get PI space and don't have (or don't want to spend) the $$$ to do BGP, or are unable to convince their upstream to cut a hole in their CIDR block and allow a 2nd party to announce that chunk (which for some is as small as /28). James H. Smith II NNCDS NNCSE Systems Engineer The Presidio Corporation
Current thread:
- DNS DOS increasing? Matt Martini (Jan 19)
- Re: DNS DOS increasing? Avleen Vig (Jan 20)
- Re: DNS DOS increasing? Alex Kamantauskas (Jan 21)
- <Possible follow-ups>
- RE: DNS DOS increasing? James Smith (Jan 21)
- RE: DNS DOS increasing? E.B. Dreger (Jan 21)
- Re: DNS DOS increasing? Joel Baker (Jan 21)
- Re: DNS DOS increasing? E.B. Dreger (Jan 21)
- RE: DNS DOS increasing? E.B. Dreger (Jan 21)
- Re: DNS DOS increasing? Avleen Vig (Jan 20)
- RE: DNS DOS increasing? Karyn Ulriksen (Jan 21)
- Re: DNS DOS increasing? Rob Evans (Jan 21)
- RE: DNS DOS increasing? James Smith (Jan 21)
- Re: DNS DOS increasing? Stephen Griffin (Jan 21)
- Re: DNS DOS increasing? E.B. Dreger (Jan 21)
- Re: DNS DOS increasing? Stephen Griffin (Jan 21)
- Re: DNS DOS increasing? Miquel van Smoorenburg (Jan 21)
- Re: DNS DOS increasing? just me (Jan 21)