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