before you go crazy check dnstracer

 # dnstracer -v old-releases.ubuntu.com  

don't forget the -v

 Tracing to old-releases.ubuntu.com[a] via 127.0.0.1, maximum of 3 retries  
 127.0.0.1 (127.0.0.1) IP HEADER  
 - Destination address: 127.0.0.1  
 DNS HEADER (send)  
 - Identifier:      0x3808  
 - Flags:        0x00 (Q )  
 - Opcode:        0 (Standard query)  
 - Return code:     0 (No error)  
 - Number questions:   1  
 - Number answer RR:   0  
 - Number authority RR: 0  
 - Number additional RR: 0  
 QUESTIONS (send)  
 - Queryname:      (12)old-releases(6)ubuntu(3)com  
 - Type:         1 (A)  
 - Class:        1 (Internet)  
 DNS HEADER (recv)  
 - Identifier:      0x3808  
 - Flags:        0x8080 (R RA )  
 - Opcode:        0 (Standard query)  
 - Return code:     0 (No error)  
 - Number questions:   1  
 - Number answer RR:   0  
 - Number authority RR: 4  
 - Number additional RR: 0  
 QUESTIONS (recv)  
 - Queryname:      (12)old-releases(6)ubuntu(3)com  
 - Type:         1 (A)  
 - Class:        1 (Internet)  
 AUTHORITY RR  
 - Domainname:      (6)ubuntu(3)com  
 - Type:         2 (NS)  
 - Class:        1 (Internet)  
 - TTL:         25923 (7h12m3s)  
 - Resource length:   6  
 - Resource data:    (3)ns1(3)p27(6)dynect(3)net  
 AUTHORITY RR  
 - Domainname:      (6)ubuntu(3)com  
 - Type:         2 (NS)  
 - Class:        1 (Internet)  
 - TTL:         25923 (7h12m3s)  
 - Resource length:   6  
 - Resource data:    (3)ns3(3)p27(6)dynect(3)net  
 AUTHORITY RR  
 - Domainname:      (6)ubuntu(3)com  
 - Type:         2 (NS)  
 - Class:        1 (Internet)  
 - TTL:         25923 (7h12m3s)  
 - Resource length:   6  
 - Resource data:    (3)ns4(3)p27(6)dynect(3)net  
 AUTHORITY RR  
 - Domainname:      (6)ubuntu(3)com  
 - Type:         2 (NS)  
 - Class:        1 (Internet)  
 - TTL:         25923 (7h12m3s)  
 - Resource length:   20  
 - Resource data:    (3)ns2(3)p27(6)dynect(3)net  
   
  |\___ ns1.p27.dynect.net [ubuntu.com] (No IP address)  
  |\___ ns3.p27.dynect.net [ubuntu.com] (No IP address)  
  |\___ ns4.p27.dynect.net [ubuntu.com] (No IP address)  
  \___ ns2.p27.dynect.net [ubuntu.com] (No IP address)