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235/715 connections in SYN_RECV state

Discussion in 'General Discussion' started by erinspice, May 12, 2007.

  1. erinspice

    erinspice Well-Known Member

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    One of my servers has 235 out of a total of 715 open connections that are in the SYN_RECV state right now. How can I terminate these connections and keep this from happening again?

    Edited to add: Now its 460 out of 1067.
     
    #1 erinspice, May 12, 2007
    Last edited: May 12, 2007
  2. gorilla

    gorilla Well-Known Member

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  3. erinspice

    erinspice Well-Known Member

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    Thanks, I've already researched SYN_RECV attacks, and tried everything I can find. I just can't find any information on terminating the TCP connections while they are in progress. My server has been like this for at least a week, maybe longer. It's causing performance issues, but the server hasn't gone down, so I'm not sure if it's an actual SYN flood attack.
     
  4. gorilla

    gorilla Well-Known Member

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    Maybe this info can help regarding your connection


    lsof | grep ESTABLISHED
    lsof | grep LISTEN
    lsof -p PID
    kill -9 PID

    have you got a firewall installed ?
     
  5. erinspice

    erinspice Well-Known Member

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    Yes. All connections in question are to port 80, Apache.
     
  6. gorilla

    gorilla Well-Known Member

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