LConrad at Go2France.com
Sun Mar 25 08:19:00 UTC 2001
>Why is it that a machine designated as a nameserver must be registered.
So its A record can be held in the root server(s). The A record for
an registered NS host is known as "glue record".
ie, for a domain, the root servers hold the "delegation data" for the
domain, aka the NS records that are delegated as authoritative for
the domain. But you can't go query the NS records unless you know
the ip for the NS records. So when the roots "refer" a requesting
resolver to a domain's NS's, the roots provide both the NS and A
records, like this:
# dig LADWP.net ns
; <<>> DiG 8.3 <<>> LADWP.net ns
;; res options: init recurs defnam dnsrch
;; got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 4
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 4
;; QUERY SECTION:
;; LADWP.net, type = NS, class = IN
;; ANSWER SECTION:
LADWP.net. 2D IN NS DNS1.ENOM.COM.
LADWP.net. 2D IN NS DNS2.ENOM.COM.
LADWP.net. 2D IN NS DNS3.ENOM.COM.
LADWP.net. 2D IN NS DNS4.ENOM.COM.
;; ADDITIONAL SECTION:
DNS1.ENOM.COM. 2D IN A 220.127.116.11
DNS2.ENOM.COM. 2D IN A 18.104.22.168
DNS3.ENOM.COM. 2D IN A 22.214.171.124
DNS4.ENOM.COM. 2D IN A 126.96.36.199
4 NS records delegated with authority for the doamin and 4 A records
as "glue". Now the resolver can refer to the A records' RDATA to
query for the domain's other records.
You should see why you can't change the ip of the NS in your zone
file without first changing the ip of the NS with your registrar /
>A seperate process from registering a domain name?
>And where is this registeration database located?
The registrar for the NS's domain, and then the registrar transfer
the NS host data to the root-servers.net.
http://MenAndMice.com/DNS-training : In Austin, TX; SFO, CA; Paris,
http://BIND8NT.MEIway.com : ISC BIND 8.2.3 "NT3" for NT4 & W2K
http://IMGate.MEIway.com : Build free, hi-perf, anti-abuse mail gateways
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