About Linux FAQ

Browse More FAQs:

Warning, got duplicate tcp line - netstat error and solution

Posted by Vivek Gite [Last updated: June 28, 2006]

Q. Whenever I run netstat command it bumps be back with an error, which read as follows:
tcp 0 0 ip-201-19-xxx-xxx.ip.s:http adsl-71-129-54-230.dsl:2249 TIME_WAIT
tcp 0 0 ip-201-19-xxx-xxx.ip.s:http ca-dstreet-cuda3-c6a-5:4380 TIME_WAIT
tcp 0 0 ip-201-19-xxx-xxx.ip.s:http ip72-199-249-17.sd.sd.:1845 TIME_WAIT
tcp 0 0 ip-201-19-xxx-xxx.ip.s:http cache-mtc-ad10.proxy.:59985 TIME_WAIT
warning, got duplicate tcp line
warning, got duplicate tcp line

Although, everything is working fine but I am little worried about this error. How do I fix this error and what does it mean?

A. This is quite uncommon. This error indicating that client/server connection are rapidly closing and reconnecting to ip ip-201-19-xxx-xxx.ip on same port 80.

To fix this problem, open /etc/sysctl.conf and

# vi /etc/sysctl.conf

Append or modify text as follows:

net.ipv4.tcp_tw_reuse = 0
net.ipv4.tcp_tw_recycle = 0

Save the file and reboot the system. If particular client IP addresses causing this problem, use the iptables to drop the client IP or block IP with null routes.

Subscribe to our free e-mail newsletter or RSS feed to get all updates. You can Email this page to a friend.

Related Other Helpful FAQs:

Discussion on This FAQ

  1. dave Says:

    # Append or modify text as follows:

    # net.ipv4.tcp_tw_reuse = 0
    # net.ipv4.tcp_tw_recycle = 0

    I did like you said, but “warning, got duplicate tcp line” still happens. What does it mean actually. Where I can find more info about the matter?

Leave a Reply

We encourage your comments, and suggestions. But please stay on topic, be polite, and avoid spam. Thank you very much for stopping by our site!

XHTML: You can use these tags: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>

*
To prove you're a person (not a spam script), type the security word shown in the picture. Click on the picture to hear an audio file of the word.
Click to hear an audio file of the anti-spam word

Copyright © 2006-2008 nixCraft. All rights reserved - TOS/Disclaimer - Privacy policy - Sitemap - Powered by Open source software.