porque dig funciona OK, mas cavar meu roteador NetGear diretamente não (enquanto o primeiro vai para ele também, porque é meu DNS, o próprio NetGear tem 8.8.8.8 definido como prim dns). Meu NetGear tem IP 192.168.1.1 na LAN. Aqui eu anexei cenário completo. Minha análise de quadros mostra IMO ambas as solicitações chegam ao roteador NetGear 192.168.1.1 na porta 53 na parte superior do UDP. Não diferem em mais nada, ou não? por favor ajude.
única diferença para além dos números de fotogramas diferentes e outras diferenças óbvias, observável para mim é
[Coloring Rule Name: UDP]
[Coloring Rule String: udp]
presente no quadro OK e a falta dele no pacote com falha (falha - não significa nenhuma resposta de 192.168.1.1)
dig cf16.eu
; <<>> DiG 9.9.2-P2 <<>> cf16.eu
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 24482
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;cf16.eu. IN A
;; ANSWER SECTION:
cf16.eu. 3600 IN A 89.75.41.50
;; Query time: 10 msec
;; SERVER: 127.0.1.1#53(127.0.1.1)
;; WHEN: Wed May 8 17:47:05 2013
;; MSG SIZE rcvd: 52
mas:
dig @192.168.1.1 cf16.eu
; <<>> DiG 9.9.2-P2 <<>> @192.168.1.1 cf16.eu
; (1 server found)
;; global options: +cmd
;; connection timed out; no servers could be reached
Pacotes Wireshark:
cavar cf16.eu [OK]
No. Time Source Destination Protocol Length Info
340 4.775113000 192.168.1.3 192.168.1.1 DNS 78 Standard query 0x5fa2 A cf16.eu
Frame 340: 78 bytes on wire (624 bits), 78 bytes captured (624 bits) on interface 0
Interface id: 0
WTAP_ENCAP: 1
Arrival Time: May 8, 2013 17:47:04.131360000 CEST
[Time shift for this packet: 0.000000000 seconds]
Epoch Time: 1368028024.131360000 seconds
[Time delta from previous captured frame: 0.005265000 seconds]
[Time delta from previous displayed frame: 0.005265000 seconds]
[Time since reference or first frame: 4.775113000 seconds]
Frame Number: 340
Frame Length: 78 bytes (624 bits)
Capture Length: 78 bytes (624 bits)
[Frame is marked: False]
[Frame is ignored: False]
[Protocols in frame: eth:ip:udp:dns]
[Coloring Rule Name: UDP]
[Coloring Rule String: udp]
Ethernet II, Src: Micro-St_4b:47:dc (d4:3d:7e:4b:47:dc), Dst: Netgear_bb:b7:2c (00:1b:2f:bb:b7:2c)
Destination: Netgear_bb:b7:2c (00:1b:2f:bb:b7:2c)
Address: Netgear_bb:b7:2c (00:1b:2f:bb:b7:2c)
.... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
.... ...0 .... .... .... .... = IG bit: Individual address (unicast)
Source: Micro-St_4b:47:dc (d4:3d:7e:4b:47:dc)
Address: Micro-St_4b:47:dc (d4:3d:7e:4b:47:dc)
.... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
.... ...0 .... .... .... .... = IG bit: Individual address (unicast)
Type: IP (0x0800)
Internet Protocol Version 4, Src: 192.168.1.3 (192.168.1.3), Dst: 192.168.1.1 (192.168.1.1)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00: Not-ECT (Not ECN-Capable Transport))
0000 00.. = Differentiated Services Codepoint: Default (0x00)
.... ..00 = Explicit Congestion Notification: Not-ECT (Not ECN-Capable Transport) (0x00)
Total Length: 64
Identification: 0xf650 (63056)
Flags: 0x00
0... .... = Reserved bit: Not set
.0.. .... = Don't fragment: Not set
..0. .... = More fragments: Not set
Fragment offset: 0
Time to live: 64
Protocol: UDP (17)
Header checksum: 0x0108 [correct]
[Good: True]
[Bad: False]
Source: 192.168.1.3 (192.168.1.3)
Destination: 192.168.1.1 (192.168.1.1)
[Source GeoIP: Unknown]
[Destination GeoIP: Unknown]
User Datagram Protocol, Src Port: 47841 (47841), Dst Port: domain (53)
Source port: 47841 (47841)
Destination port: domain (53)
Length: 44
Checksum: 0x4831 [validation disabled]
[Good Checksum: False]
[Bad Checksum: False]
Domain Name System (query)
Transaction ID: 0x5fa2
Flags: 0x0120 Standard query
0... .... .... .... = Response: Message is a query
.000 0... .... .... = Opcode: Standard query (0)
.... ..0. .... .... = Truncated: Message is not truncated
.... ...1 .... .... = Recursion desired: Do query recursively
.... .... .0.. .... = Z: reserved (0)
.... .... ..1. .... = AD bit: Set
[Expert Info (Warn/Security): AD bit set in DNS Query]
[Message: AD bit set in DNS Query]
[Severity level: Warn]
[Group: Security]
.... .... ...0 .... = Non-authenticated data: Unacceptable
Questions: 1
Answer RRs: 0
Authority RRs: 0
Additional RRs: 1
Queries
cf16.eu: type A, class IN
Name: cf16.eu
Type: A (Host address)
Class: IN (0x0001)
Additional records
<Root>: type OPT
Name: <Root>
Type: OPT (EDNS0 option)
UDP payload size: 4096
Higher bits in extended RCODE: 0x0
EDNS0 version: 0
Z: 0x0
Data length: 0
cavar 192.168.1.1 cf16.eu [falhar]
No. Time Source Destination Protocol Length Info
603 7.972662000 192.168.1.3 192.168.1.1 DNS 78 Standard query 0xc755 A cf16.eu
Frame 603: 78 bytes on wire (624 bits), 78 bytes captured (624 bits) on interface 0
Interface id: 0
WTAP_ENCAP: 1
Arrival Time: May 8, 2013 17:49:36.816366000 CEST
[Time shift for this packet: 0.000000000 seconds]
Epoch Time: 1368028176.816366000 seconds
[Time delta from previous captured frame: 0.402535000 seconds]
[Time delta from previous displayed frame: 0.402535000 seconds]
[Time since reference or first frame: 7.972662000 seconds]
Frame Number: 603
Frame Length: 78 bytes (624 bits)
Capture Length: 78 bytes (624 bits)
[Frame is marked: False]
[Frame is ignored: False]
[Protocols in frame: eth:ip:udp:dns]
Ethernet II, Src: Micro-St_4b:47:dc (d4:3d:7e:4b:47:dc), Dst: Netgear_bb:b7:2c (00:1b:2f:bb:b7:2c)
Destination: Netgear_bb:b7:2c (00:1b:2f:bb:b7:2c)
Address: Netgear_bb:b7:2c (00:1b:2f:bb:b7:2c)
.... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
.... ...0 .... .... .... .... = IG bit: Individual address (unicast)
Source: Micro-St_4b:47:dc (d4:3d:7e:4b:47:dc)
Address: Micro-St_4b:47:dc (d4:3d:7e:4b:47:dc)
.... ..0. .... .... .... .... = LG bit: Globally unique address (factory default)
.... ...0 .... .... .... .... = IG bit: Individual address (unicast)
Type: IP (0x0800)
Internet Protocol Version 4, Src: 192.168.1.3 (192.168.1.3), Dst: 192.168.1.1 (192.168.1.1)
Version: 4
Header length: 20 bytes
Differentiated Services Field: 0x00 (DSCP 0x00: Default; ECN: 0x00: Not-ECT (Not ECN-Capable Transport))
0000 00.. = Differentiated Services Codepoint: Default (0x00)
.... ..00 = Explicit Congestion Notification: Not-ECT (Not ECN-Capable Transport) (0x00)
Total Length: 64
Identification: 0xf651 (63057)
Flags: 0x00
0... .... = Reserved bit: Not set
.0.. .... = Don't fragment: Not set
..0. .... = More fragments: Not set
Fragment offset: 0
Time to live: 64
Protocol: UDP (17)
Header checksum: 0x0107 [correct]
[Good: True]
[Bad: False]
Source: 192.168.1.3 (192.168.1.3)
Destination: 192.168.1.1 (192.168.1.1)
[Source GeoIP: Unknown]
[Destination GeoIP: Unknown]
User Datagram Protocol, Src Port: 37226 (37226), Dst Port: domain (53)
Source port: 37226 (37226)
Destination port: domain (53)
Length: 44
Checksum: 0x09f5 [validation disabled]
[Good Checksum: False]
[Bad Checksum: False]
Domain Name System (query)
Transaction ID: 0xc755
Flags: 0x0120 Standard query
0... .... .... .... = Response: Message is a query
.000 0... .... .... = Opcode: Standard query (0)
.... ..0. .... .... = Truncated: Message is not truncated
.... ...1 .... .... = Recursion desired: Do query recursively
.... .... .0.. .... = Z: reserved (0)
.... .... ..1. .... = AD bit: Set
[Expert Info (Warn/Security): AD bit set in DNS Query]
[Message: AD bit set in DNS Query]
[Severity level: Warn]
[Group: Security]
.... .... ...0 .... = Non-authenticated data: Unacceptable
Questions: 1
Answer RRs: 0
Authority RRs: 0
Additional RRs: 1
Queries
cf16.eu: type A, class IN
Name: cf16.eu
Type: A (Host address)
Class: IN (0x0001)
Additional records
<Root>: type OPT
Name: <Root>
Type: OPT (EDNS0 option)
UDP payload size: 4096
Higher bits in extended RCODE: 0x0
EDNS0 version: 0
Z: 0x0
Data length: 0