Risoluzione nomi - NXDOMAIN

[Pseudonimo Stilton]

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

[Giovanni]

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/ >