At 06:53 PM 10/08/2002 -0500, Neil Johnson wrote:
>Many major net service providers (ISP's and Web Sites) try to host at least
>one of their DNS servers at different sites and on different network
>providers (some are paranoid enough to use different implementations of BIND
>and different OS platforms).
Small ISPs and small and large content providers do that.
Earthlink is one of the top 5-10 ISPs in the country,
and things work differently for carriers of their size.
Obviously any domain that wants to have reliable access
needs to have DNS servers that are geographically and logically diverse,
but while they shouldn't be on the same subnet, and should be located
where they're at least accessible from multiple BGP Autonomous Systems,
putting at least one secondary at a peering point with another big ISP
usually accomplishes that. Universities typically don't have the operational
environments to run an ISP with 24x7 99.999% uptime, and aren't in the
business of doing that commercially even if they do have a night operator.
On the other hand, they do have lots of students who enjoy, ummm,
let's call it "exploring" and "experimenting with" networks,
and seeing 1/3 of the external DNS requests from outside Earthlink
handled by a rambling wreck at Georgia Tech is a bit suspicious,
especially when it happened to be first on the list.
If they'd had a nameserver on another Tier 1 ISP, or a hosting center,
that wouldn't have been surprising at all.
>Microsoft got in trouble once because they had all their DNS servers on
>one subnet. Someone figured out if they DOS'ed the subnets router interface,
>they could basically wipe them off the net.
Yeah, that was fairly spectacular...
>My guess is mindspring has a reciprocal relationship with Georgia Tech (They
>host a DNS server for gatech.edu and gatech hosts one of theirs).
Whois service for universities is somewhat twisted these days.
Gatech.edu's primary nameservers seem to be at gatech.edu,
which is on their Class B network, plus they run the nameserver for
ns.Peach.net, which is one of the University System of Georgia's
and is on a state-owned subnet.
The traceroutes I've done to get to Gatech.edu use Qwest,
which isn't too surprising, given the Internet II stuff.
