server will not reply (syn -ack)

Posted by Brent on Server Fault See other posts from Server Fault or by Brent
Published on 2011-04-08T08:09:15Z Indexed on 2012/10/26 5:05 UTC
Read the original article Hit count: 415

Filed under:

linux

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networking

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tcp

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kernel

I like to use the following commands to manage 'TIME_WAIT', in the hope to free up resources.

echo 20 > /proc/sys/net/ipv4/tcp_fin_timeout
sysctl -w net.ipv4.tcp_tw_reuse=1
sysctl -w net.ipv4.tcp_tw_recycle=1

I found something interesting while doing a tcpdump. Sometimes if a client makes a connection (syn), the server will not reply (syn -ack).

My question is, could it be because of the top three commands.

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