After digging for a bit at arin Near as I can tell, it appears the authoritative dns servers for that specific block are a lil messed up for the moment. Not delegating something properly. Tough to say without admin access to those machines. If you check your netblock at ARIN whois, it says these two dns servers are authoritive OrgName: MCI Communications Services, Inc. d/b/a Verizon Business OrgID: MCICS Address: 22001 Loudoun County Pkwy City: Ashburn StateProv: VA PostalCode: 20147 Country: US NetRange: 208.192.0.0 - 208.255.255.255 CIDR: 208.192.0.0/10 NetName: UUNET1996B NetHandle: NET-208-192-0-0-1 Parent: NET-208-0-0-0-0 NetType: Direct Allocation NameServer: AUTH03.NS.UU.NET NameServer: AUTH00.NS.UU.NET Comment: ADDRESSES WITHIN THIS BLOCK ARE NON-PORTABLE RegDate: 1996-05-08 Updated: 2006-12-14 dig -x 208.252.226.222 @AUTH00.NS.UU.NET ; <<>> DiG 9.2.4 <<>> -x 208.252.226.222 @AUTH00.NS.UU.NET ; (1 server found) ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 47733 ;; flags: qr rd; QUERY: 1, ANSWER: 0, AUTHORITY: 2, ADDITIONAL: 1 ;; QUESTION SECTION: ;222.226.252.208.in-addr.arpa. IN PTR ;; AUTHORITY SECTION: 226.252.208.in-addr.arpa. 21600 IN NS auth02.ns.uu.net. 226.252.208.in-addr.arpa. 21600 IN NS auth20.ns.wcom.com. ;; ADDITIONAL SECTION: auth02.ns.uu.net. 3600 IN A 198.6.1.82 When you do a reverse dig at them, one of them will tell you that this ip is authoritive 198.6.1.82 aka That ip is auth02.ns.uu.net Auto03 returns squat... dig -x 208.252.226.222 @AUTH03.NS.UU.NET ; <<>> DiG 9.2.4 <<>> -x 208.252.226.222 @AUTH03.NS.UU.NET ; (1 server found) ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 32548 ;; flags: qr rd; QUERY: 1, ANSWER: 0, AUTHORITY: 2, ADDITIONAL: 0 ;; QUESTION SECTION: ;222.226.252.208.in-addr.arpa. IN PTR ;; AUTHORITY SECTION: 226.252.208.in-addr.arpa. 21600 IN NS auth02.ns.uu.net. 226.252.208.in-addr.arpa. 21600 IN NS auth20.ns.wcom.com. So, maybe something is a lil broken in their in-addr.arpa land Could be wrong though... If you dig stuff at the IP address, it seems to at least try to work though Something is not right imho dig -x 208.252.226.222 @198.6.1.82 ; <<>> DiG 9.2.4 <<>> -x 208.252.226.222 @198.6.1.82 ; (1 server found) ;; global options: printcmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 62935 ;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 0 ;; QUESTION SECTION: ;222.226.252.208.in-addr.arpa. IN PTR ;; ANSWER SECTION: 222.226.252.208.in-addr.arpa. 21600 IN CNAME 222.192.226.252.208.in-addr.arpa. ;; AUTHORITY SECTION: 192.226.252.208.in-addr.arpa. 21600 IN NS mail.sgvwater.com. Best wishes... - rh