[Dshield] RBL deaths OT?

Brian Dessent brian at dessent.net
Fri Sep 26 05:05:52 GMT 2003


Kenneth Porter wrote:
> 
> --On Thursday, September 25, 2003 4:13 PM -0400 "Jon R. Kibler"
> <Jon.Kibler at aset.com> wrote:
> 
> > There is a limit to the number of authoritative name servers a domain can
> > have (25?) which would be the weak link in any RBL's survivability.
> 
> Yes and no. The number of unique names is limited due to the size of a UDP DNS
> packet. (I think it's 12 or 13.) That's why there aren't more root servers or
> servers for a given TLD. But behind each of these names you can have a load
> balancer to expand the actual number of servers.
> 
> Of the registrars I've shopped at, most offer only 2-4 slots to enter a
> delegated name server, no more.

Yeah it looks like it's 13.  If you do a "dig spews.org soa" you'll see
13 nameservers.  GoDaddy lets you enter 13 in their nameserver
management pages, too, FWIW.

Brian




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