When I run the command ps -aux|grep -i HTTP|wc -l on a normal basis , I get
around 58 connection.When I run the command when my server cpu avg shoots to
over 1000pts , I get 1003 connections , yet when I my DC whats happening
they say my traffic is normal and I am not getting an attack.I have CSF on one server and APF on the other.When its happening I see my server load climbing , then to the 100hundred then my website gets slow until the load climbs to 2000 pts and then my site crashes .The attack seems to die down when I restart my servers though and it happens 2 times peer day.I have a dual quad core, 17 GB a RAM , linux centos 64 bit.Can you guys explain whats happening or suggest and server management company to help?

It sounds like your apache maxclients setting is far too large for your server. If you can drop this to a reasonable setting it may alleviate your problems.

Regards,

Alunduil

Well I will say you assumed correct, but I also get alot of traffic to my site.So what should I do? My settings are .

<IfModule prefork.c>
StartServers 8
MinSpareServers 5
MaxSpareServers 5
ServerLimit 6000
MaxClients 6000
MaxRequestsPerChild 6000
</IfModule>

How much RAM do you have in your server? Also, it seems that server crumbles under 2000 children but is still manageable around 1000. I would say empirically you can set that to 1024 if you want the site to stay up. If you need to increase your performance there are several places to start looking: PHP (apc and memcached), mysql (lots of stuff here), and a caching load balancer (varnish is an excellent option). If all of that isn't enough or makes things worse you'll need to look into load balancing over multiple servers as your next scalability option.

Regards,

Alunduil

I have 12 GB or RAM in the server.This is the settings I now have, is it too low?

<IfModule prefork.c>
StartServers 8
MinSpareServers 5
MaxSpareServers 5
ServerLimit 600
MaxClients 600
MaxRequestsPerChild 600
</IfModule>

Shouldn't be too low but you'll want to monitor your server over the next few days to be sure that you're not hitting MaxClients on a regular basis. If you are then you may want to bring it up and implement other optimizations if possible.

Regards,

Alunduil

So basically what matters MAXclient or MAXclient per child? And doesnt the sever limit matter?

The ServerLimit is the maximum number of children and is a hard limit. The MaxClient is the maximum number of clients that can be serviced simultaneously (which corresponds to the number of child processes). MaxRequestPerChild should remain large as that is the number of requests that process can handle before being killed and a new process taking its place.

Regards,

Alunduil