system error: warning, got duplicate tcp line

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dipsey
Posts: 2
Joined: 2005/10/20 02:26:07

system error: warning, got duplicate tcp line

Post by dipsey » 2005/10/20 09:12:22

hi guys:

I have a server,OS is CentOS3.5,apache2 and squid2.5 have beed install in it.
When I use command "netstat -na" to view the connections,I find there are many lines "warning, got duplicate tcp line."
I have google it,but I can not get reasonable answer. do anyone have find this error??
can you tell me it is a bad message...? Or don't I have to worry about a thing? so please reply!

the screen display like this:
-------------------------------------------------------------------------------------------
tcp 0 0 10.15.25.228:80 10.132.90.50:1640 ESTABLISHED
warning, got duplicate tcp line.
tcp 0 0 10.15.25.228:80 10.89.83.175:1501 TIME_WAIT
tcp 0 0 10.15.25.228:80 10.19.219.183:56839 ESTABLISHED
warning, got duplicate tcp line.
warning, got duplicate tcp line.
warning, got duplicate tcp line.
warning, got duplicate tcp line.
tcp 0 0 10.15.25.228:80 10.186.249.133:12478 ESTABLISHED
tcp 0 0 10.15.25.228:80 10.50.65.85:1697 TIME_WAIT
tcp 0 0 10.15.25.228:80 10.185.41.29:2829 ESTABLISHED
--------------------------------------------------------------------------------------------

Martijn
Posts: 5
Joined: 2005/10/26 08:44:36
Location: The Netherlands

Re: system error: warning, got duplicate tcp line

Post by Martijn » 2005/10/26 18:16:40

Dipsey,

Is your system a pretty busy system regarding to connections? I've seen it with one of our systems too. It looks like while printing the netstat -an lines new connections with the same source-port-destination-port combination are set up and therefor create the "duplicate line". I haven't had any problems with the systems, one has been running with 2500 simultanious users going through squid.

Regards,
Martijn

dipsey
Posts: 2
Joined: 2005/10/20 02:26:07

Re: system error: warning, got duplicate tcp line

Post by dipsey » 2005/11/06 07:06:44

tks!

there are about 3000 connections in the system.

i have another server use CentOS3.4 have same config with that server,but have no the warning.

it is so strange.

seeker2002
Posts: 4
Joined: 2005/05/02 20:36:34
Contact:

Re: system error: warning, got duplicate tcp line

Post by seeker2002 » 2005/12/30 05:05:06

same "problem"
warning, got duplicate tcp line.

mala
Posts: 2
Joined: 2005/02/06 16:53:19
Location: Zurich
Contact:

system error: warning, got duplicate tcp line

Post by mala » 2006/04/06 19:03:45

hi guys

please see this kb-article about this problem --> http://kbase.redhat.com/faq/FAQ_45_6180.shtm

cheers

guille
Posts: 25
Joined: 2005/11/10 17:10:14
Location: Argentina

Re: system error: warning, got duplicate tcp line

Post by guille » 2006/09/28 16:40:30

Hi everyone!

Are you sure about this ?? is a good explain...

[quote]Is your system a pretty busy system regarding to connections? I've seen it with one of our systems too. It looks like while printing the netstat -an lines new connections with the same source-port-destination-port combination are set up and therefor create the "duplicate line". I haven't had any problems with the systems, one has been running with 2500 simultanious users going through squid.[/quote]

Im not using the squid, but i still receving the messages... and i do it in my systcl.conf the instruccion of the link and same :-(

Any reasonable explication??

Cheers!!

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