Failure to retransmit? (tcpdump included)

Stephen R. van den Berg (srb@cuci.nl)
Sun, 2 Mar 1997 23:46:06 +0100

Messages sorted by: [ date ][ thread ][ subject ][ author ]
Next message: Philip Lo: "nfs error messages"
Previous message: daniel: "NNTP news reader transfer permission denied"

This is a dump of a TCP transfer that is experiencing some packet loss.
The interesting part is at the bottom (the file that is being transferred
is 1.4MB long, so the transfer is still a long way from being through at that
point). The 195.240.25.5 machine sends two acks, both, apparently, get lost.
Then it doesn't send any acks anymore for 5 minutes. The user level program
(at that point), closes the socket, and causes the connection to be
terminated.

Kernel v2.0.29 on a Pentium.
Uptime 10 days.

22:30:10.421701 198.70.117.9.80 > 195.240.25.5.1684: . 177993:179432(1439) ack 345 win 8416 (DF)
22:30:10.531701 198.70.117.9.80 > 195.240.25.5.1684: P 179432:180871(1439) ack 345 win 8416 (DF)
22:30:10.541701 195.240.25.5.1684 > 198.70.117.9.80: . ack 180871 win 15360
22:30:11.131713 198.70.117.9.80 > 195.240.25.5.1684: . 182310:183749(1439) ack 345 win 8416 (DF)
22:30:11.131713 195.240.25.5.1684 > 198.70.117.9.80: . ack 180871 win 15360
22:30:13.531738 195.240.25.5.1684 > 198.70.117.9.80: . ack 180871 win 15360
22:30:17.751787 198.70.117.9.80 > 195.240.25.5.1684: . 180871:182310(1439) ack 345 win 8416 (DF)
22:30:18.241799 195.240.25.5.1684 > 198.70.117.9.80: . ack 183749 win 15360
22:30:27.451909 198.70.117.9.80 > 195.240.25.5.1684: P 183749:185188(1439) ack 345 win 8416 (DF)
22:30:27.471909 195.240.25.5.1684 > 198.70.117.9.80: . ack 185188 win 15360
22:30:28.131921 198.70.117.9.80 > 195.240.25.5.1684: . 185188:186627(1439) ack 345 win 8416 (DF)
22:30:28.231921 198.70.117.9.80 > 195.240.25.5.1684: . 186627:188066(1439) ack 345 win 8416 (DF)
22:30:28.621921 195.240.25.5.1684 > 198.70.117.9.80: . ack 188066 win 15360
22:30:29.311934 198.70.117.9.80 > 195.240.25.5.1684: P 188066:189505(1439) ack 345 win 8416 (DF)
22:30:29.321934 195.240.25.5.1684 > 198.70.117.9.80: . ack 189505 win 15360
22:30:29.401934 198.70.117.9.80 > 195.240.25.5.1684: . 189505:190944(1439) ack 345 win 8416 (DF)
22:30:29.871939 198.70.117.9.80 > 195.240.25.5.1684: . 190944:192383(1439) ack 345 win 8416 (DF)
22:30:29.901946 195.240.25.5.1684 > 198.70.117.9.80: . ack 192383 win 15360
22:30:31.381958 198.70.117.9.80 > 195.240.25.5.1684: P 192383:193822(1439) ack 345 win 8416 (DF)
22:30:31.381958 198.70.117.9.80 > 195.240.25.5.1684: . 195261:196700(1439) ack 345 win 8416 (DF)
22:30:31.381958 195.240.25.5.1684 > 198.70.117.9.80: . ack 193822 win 14336
22:30:32.161970 198.70.117.9.80 > 195.240.25.5.1684: P 196700:198139(1439) ack 345 win 8416 (DF)
22:30:32.161970 195.240.25.5.1684 > 198.70.117.9.80: . ack 193822 win 14336
22:30:34.381995 198.70.117.9.80 > 195.240.25.5.1684: . 193822:195261(1439) ack 345 win 8416 (DF)
22:30:34.571995 195.240.25.5.1684 > 198.70.117.9.80: . ack 198139 win 15360
22:30:35.362007 198.70.117.9.80 > 195.240.25.5.1684: . 198139:199578(1439) ack 345 win 8416 (DF)
22:30:35.452007 198.70.117.9.80 > 195.240.25.5.1684: P 199578:201017(1439) ack 345 win 8416 (DF)
22:30:35.472007 195.240.25.5.1684 > 198.70.117.9.80: . ack 201017 win 15360
22:30:36.092019 198.70.117.9.80 > 195.240.25.5.1684: . 201017:202456(1439) ack 345 win 8416 (DF)
22:30:36.242019 198.70.117.9.80 > 195.240.25.5.1684: . 202456:203895(1439) ack 345 win 8416 (DF)
22:30:36.582019 195.240.25.5.1684 > 198.70.117.9.80: . ack 203895 win 15360
22:30:37.372032 198.70.117.9.80 > 195.240.25.5.1684: P 203895:205334(1439) ack 345 win 8416 (DF)
22:30:37.382032 195.240.25.5.1684 > 198.70.117.9.80: . ack 205334 win 15360
22:30:37.592032 198.70.117.9.80 > 195.240.25.5.1684: . 205334:206773(1439) ack 345 win 8416 (DF)
22:30:38.092044 195.240.25.5.1684 > 198.70.117.9.80: . ack 206773 win 15360
22:30:38.192044 198.70.117.9.80 > 195.240.25.5.1684: . 206773:208212(1439) ack 345 win 8416 (DF)
22:30:38.372044 198.70.117.9.80 > 195.240.25.5.1684: P 208212:209651(1439) ack 345 win 8416 (DF)
22:30:38.382044 195.240.25.5.1684 > 198.70.117.9.80: . ack 209651 win 15360
22:30:38.952056 198.70.117.9.80 > 195.240.25.5.1684: . 209651:211090(1439) ack 345 win 8416 (DF)
22:30:39.412056 198.70.117.9.80 > 195.240.25.5.1684: . 211090:212529(1439) ack 345 win 8416 (DF)
22:30:39.442056 195.240.25.5.1684 > 198.70.117.9.80: . ack 212529 win 15360
22:30:42.092093 198.70.117.9.80 > 195.240.25.5.1684: P 212529:213968(1439) ack 345 win 8416 (DF)
22:30:42.112093 195.240.25.5.1684 > 198.70.117.9.80: . ack 213968 win 15360
22:30:42.702093 198.70.117.9.80 > 195.240.25.5.1684: . 215407:216846(1439) ack 345 win 8416 (DF)
22:30:42.702093 195.240.25.5.1684 > 198.70.117.9.80: . ack 213968 win 15360
22:30:45.112130 195.240.25.5.1684 > 198.70.117.9.80: . ack 213968 win 15360
22:30:46.922154 198.70.117.9.80 > 195.240.25.5.1684: . 213968:215407(1439) ack 345 win 8416 (DF)
22:30:47.422154 195.240.25.5.1684 > 198.70.117.9.80: . ack 216846 win 15360
22:30:48.182166 198.70.117.9.80 > 195.240.25.5.1684: P 216846:218285(1439) ack 345 win 8416 (DF)
22:30:48.202166 195.240.25.5.1684 > 198.70.117.9.80: . ack 218285 win 15360
22:30:48.412166 198.70.117.9.80 > 195.240.25.5.1684: . 218285:219724(1439) ack 345 win 8416 (DF)
22:30:48.902178 198.70.117.9.80 > 195.240.25.5.1684: . 219724:221163(1439) ack 345 win 8416 (DF)
22:30:48.902178 195.240.25.5.1684 > 198.70.117.9.80: . ack 221163 win 15360
22:30:49.622178 198.70.117.9.80 > 195.240.25.5.1684: . 222602:224041(1439) ack 345 win 8416 (DF)
22:30:49.622178 195.240.25.5.1684 > 198.70.117.9.80: . ack 221163 win 15360
22:30:51.722203 198.70.117.9.80 > 195.240.25.5.1684: P 221163:222602(1439) ack 345 win 8416 (DF)
22:30:51.732203 195.240.25.5.1684 > 198.70.117.9.80: . ack 224041 win 15360
22:30:52.312215 198.70.117.9.80 > 195.240.25.5.1684: P 224041:225480(1439) ack 345 win 8416 (DF)
22:30:52.332215 195.240.25.5.1684 > 198.70.117.9.80: . ack 225480 win 15360
22:30:52.462215 198.70.117.9.80 > 195.240.25.5.1684: . 225480:226919(1439) ack 345 win 8416 (DF)
22:30:52.962227 195.240.25.5.1684 > 198.70.117.9.80: . ack 226919 win 14336
22:30:53.082227 198.70.117.9.80 > 195.240.25.5.1684: . 226919:228358(1439) ack 345 win 8416 (DF)
22:30:53.582227 195.240.25.5.1684 > 198.70.117.9.80: . ack 228358 win 13312
22:30:53.882237 198.70.117.9.80 > 195.240.25.5.1684: P 228358:229797(1439) ack 345 win 8416 (DF)
22:30:53.902240 195.240.25.5.1684 > 198.70.117.9.80: . ack 229797 win 15360
22:30:54.442240 198.70.117.9.80 > 195.240.25.5.1684: . 229797:231236(1439) ack 345 win 8416 (DF)
22:30:54.712240 198.70.117.9.80 > 195.240.25.5.1684: P 232675:234114(1439) ack 345 win 8416 (DF)
22:30:54.712240 195.240.25.5.1684 > 198.70.117.9.80: . ack 231236 win 15360
22:30:55.452252 198.70.117.9.80 > 195.240.25.5.1684: . 234114:235553(1439) ack 345 win 8416 (DF)
22:30:55.452252 195.240.25.5.1684 > 198.70.117.9.80: . ack 231236 win 15360
22:30:57.562276 198.70.117.9.80 > 195.240.25.5.1684: . 231236:232675(1439) ack 345 win 8416 (DF)
22:30:57.862276 195.240.25.5.1684 > 198.70.117.9.80: . ack 235553 win 15360
22:30:58.672289 198.70.117.9.80 > 195.240.25.5.1684: . 235553:236992(1439) ack 345 win 8416 (DF)
22:30:59.172301 195.240.25.5.1684 > 198.70.117.9.80: . ack 236992 win 15360
22:31:00.062313 198.70.117.9.80 > 195.240.25.5.1684: . 238431:239870(1439) ack 345 win 8416 (DF)
22:31:00.062313 195.240.25.5.1684 > 198.70.117.9.80: . ack 236992 win 15360
22:31:02.472338 195.240.25.5.1684 > 198.70.117.9.80: . ack 236992 win 15360
22:35:58.240782 195.240.25.5.1684 > 198.70.117.9.80: F 345:345(0) ack 236992 win 15360
22:35:58.600782 198.70.117.9.80 > 195.240.25.5.1684: R 242947007:242947007(0) win 0

-- Sincerely, srb@cuci.nl Stephen R. van den Berg (AKA BuGless).

E Pluribus Unix.

Next message: Philip Lo: "nfs error messages"
Previous message: daniel: "NNTP news reader transfer permission denied"