[root@asterisk1 ~]# tcpdump port 53
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on eth0, link-type EN10MB (Ethernet), capture size 96 bytes
15:48:28.293691 IP 192.168.0.2.32778 > mygateway.ar7.domain:  1053+ A? sip.axvoi              ce.com. (33)
15:48:28.309101 IP mygateway.ar7.domain > 192.168.0.2.32778:  1053 1/2/0 A sip.a              xvoice.com (96)
15:48:28.319022 IP 192.168.0.2.32778 > mygateway.ar7.domain:  42711+ PTR? 1.0.16              8.192.in-addr.arpa. (42)
15:48:28.320392 IP mygateway.ar7.domain > 192.168.0.2.32778:  42711- 1/0/0 PTR[|              domain]
15:48:28.321139 IP 192.168.0.2.32778 > mygateway.ar7.domain:  12789+ PTR? 2.0.16              8.192.in-addr.arpa. (42)
15:48:28.349311 IP 192.168.0.2.32779 > mygateway.ar7.domain:  4083+ A? freedigit              s.net. (32)
15:48:28.368407 IP mygateway.ar7.domain > 192.168.0.2.32779:  4083 1/13/13 A fre              edigits.net (501)
15:48:33.320796 IP 192.168.0.2.32778 > mygateway.ar7.domain:  12789+ PTR? 2.0.16              8.192.in-addr.arpa. (42)
15:48:38.321363 IP 192.168.0.2.32779 > mygateway.ar7.domain:  56303+ PTR? 36.130              .143.216.in-addr.arpa. (45)
15:48:38.323720 IP mygateway.ar7.domain > 192.168.0.2.32779:  56303- 1/0/0 (74)
15:48:38.324789 IP 192.168.0.2.32779 > mygateway.ar7.domain:  38475+ PTR? 160.15              9.55.67.in-addr.arpa. (44)
15:48:38.326861 IP mygateway.ar7.domain > 192.168.0.2.32779:  38475- 1/0/0 (72)
15:48:40.318659 IP mygateway.ar7.domain > 192.168.0.2.32778:  12789 ServFail- 0/              0/0 (42)
15:50:13.573336 IP 192.168.0.2.32779 > mygateway.ar7.domain:  39854+ A? sip.axvoice.com. (33)
15:50:13.575558 IP mygateway.ar7.domain > 192.168.0.2.32779:  39854- 1/0/0 A sip.axvoice.com (49)
15:50:13.763135 IP 192.168.0.2.32779 > mygateway.ar7.domain:  31216+ A? freedigits.net. (32)
15:50:13.765278 IP mygateway.ar7.domain > 192.168.0.2.32779:  31216- 1/0/0 A freedigits.net (48)