HELP - frames/packets being resent (duplicated) for Oracle sql*net connection.

From: Fuzzy <granta_at_nospam.student.canberra.edu.au>
Date: 2000/07/04
Message-ID: <39618312.9930839@newshost.interact.net.au>

Hi there,

On a particular site, I'm noticing about 20% of sql*net packets (frames) generated from an application are resent somehow ... using packet sniffer shows identical packets being resent. I know the client application in question has no control over this - it leaves all work up to Oracle's net client and ODBC.

Does anyone have any ideas why this is happening? Seen it before? Any way to track the cause?

The output below shows that they are TNS duplicates ... which is the Oracle sql*net level.

Sample of duplicate frames

• - - - - - - - - - - - - - - - - - - - Frame 4831 - - - - - - - - - -
• - - - - - - - - - Frame Status Source Address Dest. Address Size Rel. Time Delta Time Abs. Time Summary 4831 [<valid - I've blanked these out for obvious reasons>] [<valid - I've blanked these out for obvious reasons>] 235 0:05:12.835 0.002.035 06/09/2000 01:11:15 PM SQL: OALL7 - Fast UPI call to opial7 DLC: ----- DLC Header ----- DLC: DLC: Frame 4831 arrived at 13:11:15.6540; frame size is 235 (00EB hex) bytes. DLC: Destination = Station 00107B686221 DLC: Source = Station Intel 1372A4 DLC: Ethertype = 0800 (IP) DLC: IP: ----- IP Header ----- IP: IP: Version = 4, header length = 20 bytes IP: Type of service = 00 IP: 000. .... = routine IP: ...0 .... = normal delay IP: .... 0... = normal throughput IP: .... .0.. = normal reliability IP: Total length = 221 bytes IP: Identification = 25439 IP: Flags = 4X IP: .1.. .... = don't fragment IP: ..0. .... = last fragment IP: Fragment offset = 0 bytes IP: Time to live = 128 seconds/hops IP: Protocol = 6 (TCP) IP: Header checksum = 8459 (correct) IP: Source address = [<valid - I've blanked these out for obvious reasons>] IP: Destination address = [<valid - I've blanked these out for obvious reasons>] IP: No options IP: TCP: ----- TCP header ----- TCP: TCP: Source port = 1236 TCP: Destination port = 4798 TCP: Sequence number = 9560996 TCP: Next expected Seq number= 9561177 TCP: Acknowledgment number = 2917434459 TCP: Data offset = 20 bytes TCP: Flags = 18 TCP: ..0. .... = (No urgent pointer) TCP: ...1 .... = Acknowledgment TCP: .... 1... = Push TCP: .... .0.. = (No reset) TCP: .... ..0. = (No SYN) TCP: .... ...0 = (No FIN) TCP: Window = 7846 TCP: Checksum = 0037 (correct) TCP: No TCP options TCP: [181 Bytes of data] TCP: TNS: ----- Transparent Network Substrate Protocol ----- TNS: TNS: Packet length = 181 TNS: Packet checksum = 0000 (Reserved) TNS: TNS packet type = 6 (Data) TNS: Packet flags = 00 TNS: .... ...0 = (Not used prior to TNS version 3) TNS: Header checksum = 0000 (Reserved) TNS: Data flag = 0 (No bits set) TNS: [171 byte(s) of data] TNS: SQL: ----- SQL*Net Data ----- SQL: SQL: Basic operation = 3 (User to Oracle (UPI) request) SQL: Function type = 71 (OALL7 - Fast UPI call to opial7) SQL: Sequence number = 41 SQL: Fast UPI options = 0x8050 SQL: Fast UPI Option1 = 50 SQL: 0... .... = (No cancel after fetch) SQL: .1.. .... = Fetch to be performed SQL: ..0. .... = (No execute to be performed) SQL: ...1 .... = Define to be performed SQL: .... 0... = (No bind to be performed) SQL: .... ...0 = (No parse to be performed) SQL: Fast UPI Option2 = 80 SQL: 1... .... = Statement is not PL/SQL SQL: .0.. .... = (No parse required) SQL: .... .0.. = (Don't send I/O vector back) SQL: .... ..0. = (Non-exact fetch) SQL: .... ...0 = (No commit) SQL: Cursor number = 2 SQL: SQL text address = 0x0000 SQL: SQL text length = 0 SQL: DBlink text address = 0x0000 SQL: DBlink text length = 0 SQL: ADDR HEX ASCII 0000: 00 10 7b 68 62 21 00 90 27 13 72 a4 08 00 45 00 | .{hb!.'.r¤..E. 0010: 00 dd 63 5f 40 00 80 06 84 59 ca 0e bf 38 c1 09 | Ýc_@.€.„YÊ.¿8Á 0020: c8 11 04 d4 12 be 00 91 e3 a4 ad e4 84 5b 50 18 | È..Ô.¾.‘㤭ä„[P. 0030: 1e a6 00 37 00 00 00 b5 00 00 06 00 00 00 00 00 | ¦.7...µ........ 0040: 03 47 29 50 80 00 00 02 00 00 00 00 00 00 00 00 | G)P€........... 0050: 00 00 00 00 00 00 00 00 00 00 00 e0 75 76 01 07 |
  ..........àuv..
  0060: 00 00 00 dc 74 87 01 02 00 00 00 00 00 00 00 1c |
  ..Üt‡..........
  0070: 9c 87 01 05 00 00 00 00 00 00 00 00 00 00 00 00 | œ‡.............. 0080: 00 00 00 6b 01 00 00 00 00 00 00 00 00 00 00 00 |
  ..k............
  0090: 00 00 00 00 00 00 00 00 00 00 00 01 03 00 00 29 |
  ..............)
  00a0: 00 00 00 00 00 00 00 00 00 00 00 01 03 00 00 29 |
  ..............)
  00b0: 00 00 00 00 00 00 00 00 00 00 00 01 03 00 00 02 |
  ...............
  00c0: 00 00 00 00 00 00 00 00 00 00 00 01 03 00 00 29 |
  ..............)
  00d0: 00 00 00 00 00 00 00 00 00 00 00 01 03 00 00 29 |
  ..............)
  00e0: 00 00 00 00 00 00 00 00 00 00 00 | ...........
• - - - - - - - - - - - - - - - - - - - Frame 4832 - - - - - - - - - -
• - - - - - - - - - Frame Status Source Address Dest. Address Size Rel. Time Delta Time Abs. Time Summary 4832 # [<valid - I've blanked these out for obvious reasons>] [<valid - I've blanked these out for obvious reasons>] 235 0:05:13.039 0.203.981 06/09/2000 01:11:15 PM Expert: Retransmission

TNS: duplicate of frame 4831
DLC: ----- DLC Header -----

      DLC:  
      DLC:  Frame 4832 arrived at  13:11:15.8580; frame size is 235
(00EB hex) bytes.
      DLC:  Destination = Station 00107B686221
      DLC:  Source      = Station Intel 1372A4
      DLC:  Ethertype   = 0800 (IP)
      DLC:  
IP: ----- IP Header -----
      IP: 
      IP: Version = 4, header length = 20 bytes
      IP: Type of service = 00
      IP:       000. ....   = routine
      IP:       ...0 .... = normal delay
      IP:       .... 0... = normal throughput
      IP:       .... .0.. = normal reliability
      IP: Total length    = 221 bytes
      IP: Identification  = 25695
      IP: Flags           = 4X
      IP:       .1.. .... = don't fragment
      IP:       ..0. .... = last fragment
      IP: Fragment offset = 0 bytes
      IP: Time to live    = 128 seconds/hops
      IP: Protocol        = 6 (TCP)
      IP: Header checksum = 8359 (correct)
      IP: Source address      = [<valid - I've blanked these out for
obvious reasons>]
      IP: Destination address = [<valid - I've blanked these out for
obvious reasons>]
      IP: No options
      IP: 
TCP: ----- TCP header -----
      TCP: 
      TCP: Source port             = 1236
      TCP: Destination port        = 4798
      TCP: Sequence number         = 9560996
      TCP: Next expected Seq number= 9561177
      TCP: Acknowledgment number   = 2917434459
      TCP: Data offset             = 20 bytes
      TCP: Flags                   = 18
      TCP:               ..0. .... = (No urgent pointer)
      TCP:               ...1 .... = Acknowledgment
      TCP:               .... 1... = Push
      TCP:               .... .0.. = (No reset)
      TCP:               .... ..0. = (No SYN)
      TCP:               .... ...0 = (No FIN)
      TCP: Window                  = 7846
      TCP: Checksum                = 0037 (correct)
      TCP: No TCP options
      TCP: [181 Bytes of data]
      TCP: 

TNS: ----- Transparent Network Substrate Protocol duplicate Frame

---

      TNS: 
      TNS: Duplicate of frame: 4831
      TNS: 
      TNS: [181 bytes data]
      TNS: 
ADDR  HEX                                               ASCII

0000: 00 10 7b 68 62 21 00 90 27 13 72 a4 08 00 45 00 | .{hb!.'.r¤..E.
0010: 00 dd 64 5f 40 00 80 06 83 59 ca 0e bf 38 c1 09 | Ýd_@.€.ƒYÊ.¿8Á
0020: c8 11 04 d4 12 be 00 91 e3 a4 ad e4 84 5b 50 18 | È..Ô.¾.‘㤭ä„[P.
0030: 1e a6 00 37 00 00 00 b5 00 00 06 00 00 00 00 00 | ¦.7...µ........
0040: 03 47 29 50 80 00 00 02 00 00 00 00 00 00 00 00 | G)P€...........
0050: 00 00 00 00 00 00 00 00 00 00 00 e0 75 76 01 07 |
..........àuv..

0060: 00 00 00 dc 74 87 01 02 00 00 00 00 00 00 00 1c |
..Üt‡..........

0070: 9c 87 01 05 00 00 00 00 00 00 00 00 00 00 00 00 | œ‡..............
0080: 00 00 00 6b 01 00 00 00 00 00 00 00 00 00 00 00 |
..k............

0090: 00 00 00 00 00 00 00 00 00 00 00 01 03 00 00 29 |
..............)

00a0: 00 00 00 00 00 00 00 00 00 00 00 01 03 00 00 29 |
..............)

00b0: 00 00 00 00 00 00 00 00 00 00 00 01 03 00 00 02 |
...............

00c0: 00 00 00 00 00 00 00 00 00 00 00 01 03 00 00 29 |
..............)

00d0: 00 00 00 00 00 00 00 00 00 00 00 01 03 00 00 29 |
..............)

00e0: 00 00 00 00 00 00 00 00 00 00 00                | ...........

Help!

Ciao
Fuzzy
#;-) Received on Tue Jul 04 2000 - 00:00:00 CDT