–> DNS

1. Run nslookup to obtain the IP address of a Web server in Asia.

[alex@alex-EasyNote:~]$ nslookup nic.ae

Server: 62.101.93.101
Address: 62.101.93.101#53

Non-authoritative answer:
Name: nic.ae
Address: 213.42.0.168
Name: nic.ae
Address: 195.229.242.240

2. Run nslookup to determine the authoritative DNS servers for a university in Europe.

[alex@alex-EasyNote:~]$ nslookup -type=NS uniroma1.it

Server: 62.101.93.101
Address: 62.101.93.101#53

Non-authoritative answer:
uniroma1.it nameserver = risc-ns.cics.uniroma1.it.
uniroma1.it nameserver = desiree.cics.uniroma1.it.
uniroma1.it nameserver = ns1.garr.net.

Authoritative answers can be found from:
ns1.garr.net internet address = 193.206.141.38
ns1.garr.net has AAAA address 2001:760:ffff:ffff::aa
desiree.cics.uniroma1.it internet address = 151.100.4.13
risc-ns.cics.uniroma1.it internet address = 151.100.4.2

3. Run nslookup so that one of the DNS servers obtained in Question 2 is queried for the mail servers for Yahoo! mail.

[alex@alex-EasyNote:~]$ dig yahoo.com MX +noall +answer

; <<>> DiG 9.7.3 <<>> yahoo.com MX +noall +answer
;; global options: +cmd
yahoo.com. 420 IN MX 1 mta7.am0.yahoodns.net.
yahoo.com. 420 IN MX 1 mta5.am0.yahoodns.net.
yahoo.com. 420 IN MX 1 mta6.am0.yahoodns.net.

[alex@alex-EasyNote:~]$ nslookup mta7.am0.yahoodns.net ns1.garr.net

Server: ns1.garr.net
Address: 193.206.141.38#53

** server can’t find mta7.am0.yahoodns.net.fastwebnet.it: REFUSED
viene falsato dai router di fastweb

Potete scaricare il file con la spiegazione e gli altri esercizi qui: Wireshark_DNS_Sept_15_2009

RFC 1034

wlan0 - Wireshark_007