i have blocked a zone enumerator, though i guess they will be a whack-a-mole others have reported them as well /home/randy> sudo tcpdump -pni vtnet0 -c 10 port 53 and net 193.235.141 tcpdump: verbose output suppressed, use -v or -vv for full protocol decode listening on vtnet0, link-type EN10MB (Ethernet), capture size 262144 bytes 22:42:39.516849 IP 193.235.141.90.32768 > 666.42.7.11.53: 14 NS? 33j4h.org.al. (30) 22:42:39.517640 IP 193.235.141.17.32768 > 666.42.7.11.53: 14 NS? 33m6d.xn--mgbayh7gpa. (38) 22:42:39.519169 IP 193.235.141.17.32768 > 666.42.7.11.53: 14 NS? 33lxd.tn. (26) 22:42:39.520064 IP 193.235.141.171.32768 > 666.42.7.11.53: 14 NS? 33md6.jo. (26) 22:42:39.521081 IP 193.235.141.247.32768 > 666.42.7.11.53: 14 NS? 33lxd.lb. (26) 22:42:39.523981 IP 193.235.141.162.32768 > 666.42.7.11.53: 14 NS? 33pd2.az. (26) 22:42:39.525043 IP 193.235.141.60.32768 > 666.42.7.11.53: 14 NS? 33nc5.com.al. (30) 22:42:39.526185 IP 193.235.141.209.32768 > 666.42.7.11.53: 14 NS? 33nc5.sz. (26) 22:42:39.527931 IP 193.235.141.150.32768 > 666.42.7.11.53: 14 NS? 33q5p.com.al. (30) 22:42:39.529516 IP 193.235.141.210.32768 > 666.42.7.11.53: 14 NS? 33qbq.com.al. (30) 10 packets captured 124 packets received by filter 0 packets dropped by kernel inetnum: 193.235.141.0 - 193.235.141.255 netname: domaincrawler-hosting descr: domaincrawler hosting org: ORG-ABUS1196-RIPE country: SE admin-c: VIJE1-RIPE tech-c: VIJE1-RIPE status: ASSIGNED PA notify: c+1196@resilans.se mnt-by: RESILANS-MNT mnt-routes: ETTNET-LIR created: 2008-04-03T11:21:00Z last-modified: 2017-04-10T12:47:06Z source: RIPE randy