> >
> > We have a sporadic problem with qmail hanging and eventually
> timing out when
> > popping certain messages.
>
I just saw this problem again. Ran tcpdump and captured the pop-3
conversation below. What's interesting is that client is only retrieving 1
message, instead of the 7 present. The server sends the message, the client
acks it, but then doesn't request any more messages. So, apparently the
server is waiting for the next command and not getting it. On the other
hand, the client is apparently expecting more data, but not getting it, or
it's confused about how many messages it's received, so the client times out
and sends a FIN packet.
Carey
20:55:04.168387 < client > server: S 595822:595822(0)
20:55:04.168410 > server > client: S 1790652965:1790652965(0) ack 595823
20:55:04.356445 < client > server: . 1:1(0) ack 1
20:55:04.861660 > server > client: P 1:46(45) ack 1 [+OK
<25027.985316104@xxxxxxx>]
20:55:05.043873 < client > server: P 1:15(14) ack 46 [USER xxxxxxx]
20:55:05.043927 > server > client: . 46:46(0) ack 15 ack
20:55:05.044035 > server > client: P 46:52(6) ack 15 [+OK ]
20:55:05.211407 < client > server: P 15:26(11) ack 52 [PASS xxxxxxxx]
20:55:05.221566 > server > client: P 52:58(6) ack 26 [+OK ]
20:55:05.385687 < client > server: P 26:32(6) ack 58 [STAT]
20:55:05.385823 > server > client: P 58:72(14) ack 32 [+OK 7 123284]
20:55:05.727457 < client > server: P 32:38(6) ack 72 [UIDL]
20:55:05.727545 > server > client: P 72:78(6) ack 38 [+OK ]
20:55:05.727596 > server > client: P 78:366(288) ack 38 [UIDL data...]
20:55:05.961556 < client > server: . 38:38(0) ack 366
20:55:06.141839 < client > server: P 38:46(8) ack 366 [RETR 1]
20:55:06.141928 > server > client: P 366:372(6) ack 46 [+OK ]
20:55:06.142022 > server > client: P 372:908(536) ack 46 [536 bytes, message
1 data...]
20:55:06.142036 > server > client: P 908:1352(444) ack 46 [444 bytes,
message 1 data...]
20:55:06.142107 > server > client: P 1352:1888(536) ack 46 [536 bytes,
message 1 data...]
20:55:06.142119 > server > client: P 1888:2349(461) ack 46 [461 bytes,
message 1 data...]
20:55:06.142196 > server > client: P 2349:2885(536) ack 46 [536 bytes,
message 1 data...]
20:55:06.142208 > server > client: P 2885:3313(428) ack 46 [428 bytes,
message 1 data...]
20:55:06.679129 < client > server: . 46:46(0) ack 908
20:55:06.679162 > server > client: P 3313:3849(536) ack 46 [536 bytes,
message 1 data...]
20:55:06.687235 < client > server: . 46:46(0) ack 1888
20:55:06.869646 < client > server: . 46:46(0) ack 2885
20:55:07.024157 < client > server: . 46:46(0) ack 3849
20:55:07.024181 > server > client: P 3849:3851(2) ack 46 [2 bytes, message 1
data]
20:55:07.573063 < client > server: . 46:46(0) ack 3851 [all data acked]
20:56:01.567188 < client > server: F 46:46(0) ack 3851 [client sends FIN]
20:56:01.567214 > server > client: . 3851:3851(0) ack 47
20:56:01.567419 > server > client: F 3851:3851(0) ack 47 [server sends FIN]
20:56:01.777954 < client > server: . 47:47(0) ack 3852
