about TCP connection


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# 1  
Error about TCP connection

Hi Experts,

need help about release or refresh TCP Connection:

i have the sample like below :

application log connection:
0500 ( 192.168.0.1:36053) 00919 2007/05/10 23:30:25 112 13 2007/05/10 23:30:25 1969/12/31 17:00:00
0500 ( 192.168.0.1:36054) 00920 2007/05/10 23:30:26 000 00 1969/12/31 17:00:00 1969/12/31 17:00:00
0500 ( 192.168.0.1:36055) 00921 2007/05/10 23:30:26 000 00 1969/12/31 17:00:00 1969/12/31 17:00:00
0500 ( 192.168.0.1:42699) 00314 2007/05/14 07:07:23 097 13 2007/05/14 07:07:23 1969/12/31 17:00:00
0500 ( 192.168.0.1:36057) 00923 2007/05/10 23:30:26 000 00 1969/12/31 17:00:00 1969/12/31 17:00:00
0500 ( 192.168.0.1:49175) 26426 2007/05/10 23:54:46 000 00 1969/12/31 17:00:00 1969/12/31 17:00:00

netstat -a | grep 500
hostname.500 192.168.0.1.36053 16560 0 66608 0 ESTABLISHED
hostname.500 192.168.0.1.36054 5840 0 66608 0 ESTABLISHED
hostname.500 192.168.0.1.36055 5840 0 66608 0 ESTABLISHED
hostname.500 192.168.0.1.36057 5840 0 66608 0 ESTABLISHED
hostname.500 192.168.0.1.36067 5840 0 66608 0 ESTABLISHED
hostname.500 192.168.0.1.36073 16560 0 66608 0 ESTABLISHED


the application connection its connect through port 500 to another application, but if we see the bold one is mean that the tcp connection not binded to the another application server.

how to release or refresh the tcp connection to not bind "bold" ?

please advices

thank you

bucci
# 2  
Give us header of "application log connection:". Example
Local-Port Remote-IP:Port ??? Connection-Time ??? ?? ????
0500 ( 192.168.0.1:36053) 00919 2007/05/10 23:30:25 112 13 2007/05/10 23:30:25 1969/12/31 17:00:00

pseudo code of your server will be very helpful to help you

You can use tcpdump/ethereal to see what is happening b/w both client and server... Simply "snoop" packets for "port 500".

At instance i can think of tunning Kernel-TCP/IP parameters and reduce idle-timeout. In SunOs you can use ndd and in Linux you can use sysctl (/proc/sys/net/ipv4)

All the best.
# 3  
Hi Sumitpandya,

local-port is 500 and remote port is depend on the application is can 36053, 45050,etc and connection time is 23:30:25, pid is 00919 (919), application id is 112.

how to check that the tcp connection is stuck (means no transaction on the TCP ?

note : using solaris 8 sparc 5.8

please advice

Thank you

bucci

Quote:
Originally Posted by sumitpandya
Give us header of "application log connection:". Example
Local-Port Remote-IP:Port ??? Connection-Time ??? ?? ????
0500 ( 192.168.0.1:36053) 00919 2007/05/10 23:30:25 112 13 2007/05/10 23:30:25 1969/12/31 17:00:00

pseudo code of your server will be very helpful to help you

You can use tcpdump/ethereal to see what is happening b/w both client and server... Simply "snoop" packets for "port 500".

At instance i can think of tunning Kernel-TCP/IP parameters and reduce idle-timeout. In SunOs you can use ndd and in Linux you can use sysctl (/proc/sys/net/ipv4)

All the best.
# 4  
Run snoop command

Quote:
Originally Posted by bucci
Hi Sumitpandya,

local-port is 500 and remote port is depend on the application is can 36053, 45050,etc and connection time is 23:30:25, pid is 00919 (919), application id is 112.

how to check that the tcp connection is stuck (means no transaction on the TCP ?

note : using solaris 8 sparc 5.8

please advice

Thank you

bucci
# snoop -r -s 1600 "port 500"
should give you communication b/w server and client. Then you analyse the sequence for communication taking place. If you running client and server on same machine then you need to provide extra option " -d lo0 ". Additionally you can write that output to a file using one more option " -o snoop500.pcap " and then use "Ethereal" tool to further analyse commuication
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