>> My web server's response time for http requests skyrockets every >> weekday between about 9am and 5pm. I've gone over my munin graphs and >> the only one that really correlates well with the slowdown is "TCP >> Queuing". It looks like I normally have about 400 packets per second >> graphed as "direct copy from queue" in munin throughout the day, but 2 >> to 3.5 times that many are periodically graphed during work hours. I >> don't see the same pattern at all from the graph of all traffic on my >> network interface which actually peaks over the weekend. TCP Queuing >> doesn't rise above 400 packets per second all weekend. This is >> consistent week after week. >> >> My two employees come into work during the hours in question, and they >> certainly make frequent requests of the web server while at work, but >> if their volume of requests were the cause of the problem then that >> would be reflected in the graph of web server requests but it is not. >> I do run a small MTU on the systems at work due to the config of the >> modem/router we have there. >> >> Is this a recognizable problem to anyone? > > > I'm in the midst of this. Are there certain attacks I should check for?
It looks like the TCP Queuing spike itself was due to imapproxy which I've now disabled. I'll post more info as I gather it. - Grant
