Possible SYN flooding on port 80. Sending cookies.

Possible SYN flooding on port 80. Sending cookies

This happens to be the message on my Debian Lenny.
What could be the reason.. the server is extremely slow and not processing any requests.

Help me fix it.

 

Install CSF (config server security & firewall).

 

thanks .. shall try it out

 

With CSF you can limit the number of total connection configuring CT_LIMIT.. but to STOP syn flood on port 80 using apache you must to install mod_qos. With that mod you can stop for sure any type of abuse of apache. just setting QS_SrvMaxConnPerIP 25 and each IP can only use 25 connection without be blocked. with CSF is you se CT_LIMIT = 25 if you open 26 connection your IP will be banned for total service of server. also ping..

Try and lwt me know

 

I am having such a attack. I have installed csf and changed the settings. But still site is very slow.
How to install mod_qos on centos 6?

 

Have you looked into SynFlood control settings? Kernel hardening?