Warning, got duplicate tcp line - netstat error and solution
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.
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March 29th, 2007 at 8:23 am
# 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?