Tecnología de redes. Internet (página 2)

Partes: 1, 2

Archivo de Zona
@ IN SOA phloem.uoregon.edu. hostmaster.phloem.uoregon.edu. (
1999060900 ; Serial number (yyyymmddnn)
7200 ; Refresh /* 2 hours */
900 ; Retry /* 15 minutes */
604800 ; Expire /* 7 days */
86400 ; Minimum TTL /* 1 day */
)

@ IN NS phloem.uoregon.edu.
@ IN NS ruminant.uoregon.edu.
@ IN NS dns.cs.uoregon.edu.
@ IN NS arizona.edu.
@ IN TXT "LOC: Lat 44.02.781 Lon 123.04.699"

cs IN NS phloem.uoregon.edu.
cs IN NS dns.cs.uoregon.edu.

www.physics IN CNAME zebu.uoregon.edu.
ftp 3600 IN CNAME sap.uoregon.edu.
cisco2-gw IN CNAME cisco2-gw.cs.uoregon.edu.
irs.sch IN CNAME irs.osshe.edu.

localhost IN A 127.0.0.1

uoregon.edu. IN MX 0 network-services.uoregon.edu.

Archivo de Zona (cont.)
cisco1-gw IN A 128.223.2.1
IN A 128.223.3.1
IN A 128.223.30.1

alpha 0 IN A 128.223.142.106
0 IN A 128.223.142.113

zebu IN A 128.223.21.25
IN MX 0 zebu.uoregon.edu.

pagelabmac IN A 128.223.20.121
IN HINFO Mac OpenTransport
IN TXT "Ethernet: 00059A20C5BB"
IN TXT "DL: 10000"
IN TXT "LOC: 381 Klamath"
IN TXT "CON: Grace Ann Neff, 346-4652"

$origin sch.uoregon.edu.
opal IN A 128.223.28.19

$ORIGIN rrp.net.
inet IN A 128.223.56.241
$ORIGIN uoregon.edu.

BIND
Berkeley Internet Name Domain
Quizas la implementación más popular de DNS.
Mantenida por http://www.isc.org
Utiliza los archivos antes mencionado y un archivo de inicialización/configuración del sistema (named.conf)

El Archivo de Configuración de BIND v8
options {
directory "/etc/named";
allow-transfer {
128.223.21.15;
};
fake-iquery yes;
};

zone "." {
type hint;
file "named.root";
};

zone "uoregon.edu" {
type master;
file "uo.zone";
};

zone "223.128.in-addr.arpa" {
type master;
file "uo.rev";
};

zone "0.0.127.in-addr.arpa" {
type master;
file "named.local";
};

zone "rrp.net" {
type master;
file "uo.zone";
};

zone "cs.uoregon.edu" {
type slave;
file "cs.uoregon.edu";
masters {
128.223.6.9;
};
};

zone "bethel.k12.or.us" {
type slave;
file "bethel.k12.or.us";
masters {
163.41.16.10;
};
};

NSLOOKUP
Ahora que tenemos todo configurado, podemos poner a funcionar nuestro DNS.
Un utilitario de mucha ayuda para ver si todo está funcionando correctamente es nslookup.
Nslookup es un cliente de DNS. Podemos utilizarlos para hacer preguntas sobre registros específicos de determinadas estaciones.

NSLOOKUP (Ejemplo)
[jad@phloem:/etc] 23% nslookup
Default Server: phloem.uoregon.edu
Address: 128.223.32.35

> alien
Server: phloem.uoregon.edu
Address: 128.223.32.35

alien.uoregon.edu preference = 0, mail exchanger = network-services.uoregon.edu
alien.uoregon.edu internet address = 128.223.60.70
uoregon.edu nameserver = phloem.uoregon.edu
uoregon.edu nameserver = ruminant.uoregon.edu
uoregon.edu nameserver = dns.cs.uoregon.edu
uoregon.edu nameserver = arizona.edu
network-services.uoregon.edu internet address = 128.223.60.21
phloem.uoregon.edu internet address = 128.223.32.35
ruminant.uoregon.edu internet address = 128.223.21.15
dns.cs.uoregon.edu internet address = 128.223.6.9
arizona.edu internet address = 128.196.128.233

NSLOOKUP (Ejemplo)
[jad@phloem:/etc] 23% nslookup
Default Server: phloem.uoregon.edu
Address: 128.223.32.35

> set type=ptr
> 128.223.60.70
Server: phloem.uoregon.edu
Address: 128.223.32.35

70.60.223.128.in-addr.arpa name = alien.uoregon.edu
223.128.in-addr.arpa nameserver = phloem.uoregon.edu
223.128.in-addr.arpa nameserver = ruminant.uoregon.edu
223.128.in-addr.arpa nameserver = dns.cs.uoregon.edu
223.128.in-addr.arpa nameserver = arizona.edu
phloem.uoregon.edu internet address = 128.223.32.35
ruminant.uoregon.edu internet address = 128.223.21.15
dns.cs.uoregon.edu internet address = 128.223.6.9
arizona.edu internet address = 128.196.128.233

Referencias
DNS and BIND. Paul Albitz.
Tcp/IP Network Administración. Craig Hunt.
Managing IP Networks with Cisco Routers. Scott M. Ballew.
http://www.cis.ohio-state.edu/hypertext/information/rfc.html
RFC-1035 DNS Implementation
RFC-1591 DNS Structure & Delegation
RFC-2182 Selection and Operation of Secondary DNS Servers
RFC-2535 DNS Security Extensions