I have this server that serves some media ads (graphics files) with heavy traffic and a few websites that is not heavy traffic. I have also installed ISPconfig 3 (version 18.104.22.168) on it. Using ubuntu 8.04.4. Lately, this server is very unresponsive. I don't know what happened cause suddenly the server's http is very unresponsive. I tried looking into all the log files but was unable to find the solution. Apache service is up and down. One thing I found in the log is apache saying some error about maxclients reached. Ask me to increase. However, the maxclients is already at 700. I increased it to 800 and then 1000 and I still get the error after only mere minutes of restarting apache service. Then I look into apache server-status and see lots of thread in apache that is in "K". It means still in keepalive. That is probably why the maclients used up so quickly. Then I turned keepalive OFF. No more apache PID in "K" but http is still up and down. Anyone have any idea what else to look? Is it someone attacking my apache service?