Newsgroup: it.comp.reti.ip-admin
Titolo: Risoluzione nomi -  NXDOMAIN

Ciao,
sto cercando di configurare sshd e tcp wrapper per accettare connessioni solo
da un dato dominio, ma non riesco a fare funzionare la cosa perche non
risolve l'indirizzo.
 
Ho IP 62.102.XXX.XXX, se eseguio dig -x IP ottengo
host-116-155-XXX-XXX.net.provider.net
.
 
Se eseguo dig 
host-116-155-XXX-XXX.net.provider.net
., ottengo:
 
; <<>> DiG 9.10.3-P4-Debian <<>> 
host-116-155-XXX-XXX.net.provider.net
.
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 29162
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1
 
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;
host-116-155-XXX-XXX.net.provider.net
. IN	A
 
;; Query time: 0 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Fri Aug 03 23:41:39 CEST 2018
;; MSG SIZE  rcvd: 63
 
Se eseguo host -d 
host-116-155-XXX-XXX.net.provider.net
. ottengo
 
Trying "
host-116-155-XXX-XXX.net.provider.net
."
Host 
host-116-155-XXX-XXX.net.provider.net
. not found: 3(NXDOMAIN)
Received 52 bytes from 127.0.0.1#53 in 0 ms
Received 52 bytes from 127.0.0.1#53 in 0 ms
 
Se indico ad host o a dig un server diverso dal dnsmasq che ho sulla
macchina il risultato non cambia.
 
Chiedo lumi
Grazie


Mi sembra una situazione generalizzata anche se non so spiegarne la 
ragione.  Molti provider hanno un comportamento analogo dei loro i loro 
dns per gli IP assegnati dinamicamente.
 
$ lsodgf0@marina:~ > dig -t a 
ppp-222-219.20-151.wind.it
.
 
; <<>> DiG 9.10.8 <<>> -t a 
ppp-222-219.20-151.wind.it
.
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 17771
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 1, ADDITIONAL: 1
 
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1492
;; QUESTION SECTION:
;
ppp-222-219.20-151.wind.it
.    IN      A
 
;; AUTHORITY SECTION:
wind.it
.                3600    IN      SOA     
dns.wind.it
. 
root.dns.wind.it
. 
2018080101
 86400 14400 604800 3600
 
;; Query time: 53 msec
;; SERVER: 192.168.217.130#53(192.168.217.130)
;; WHEN: Sat Aug 04 08:35:16 MEST 2018
;; MSG SIZE  rcvd: 100
 
$ lsodgf0@marina:~ > dig -x 151.20.219.222
 
; <<>> DiG 9.10.8 <<>> -x 151.20.219.222
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 32826
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 3
 
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1492
;; QUESTION SECTION:
;222.219.20.151.in-addr.arpa.   IN      PTR
 
;; ANSWER SECTION:
222.219.20.151.in-addr.arpa. 86400 IN   PTR     
ppp-222-219.20-151.wind.it
.
 
;; AUTHORITY SECTION:
20.151.in-addr.arpa.    172800  IN      NS      
ns.iunet.it
.
20.151.in-addr.arpa.    172800  IN      NS      
ns.infuturo.it
.
 
;; ADDITIONAL SECTION:
ns.iunet.it
.            10800   IN      A       192.106.1.1
ns.infuturo.it
.         10800   IN      A       192.106.1.9
 
;; Query time: 199 msec
;; SERVER: 192.168.217.130#53(192.168.217.130)
;; WHEN: Sat Aug 04 08:34:23 MEST 2018
;; MSG SIZE  rcvd: 177
 
$ lsodgf0@marina:~ >
 
 
Ciao
Giovanni
-- 
   A computer is like an air conditioner,
   it stops working when you open Windows.
   < 
http://giovanni.homelinux.net/
 >