Denial of service attack, is an attempt through some means to make a computer or network resource unavailable.

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Best way to use large IP blacklist to deny access to a Windows 2008 web server?

Basically, I'm looking for a solution similar to the ones mentioned in a similar (but Linux-focussed thread) located here so that I can deny access to blacklisted IPs. I am specifically focussed on ...
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Finding Evidence of a Denial of Service Attack (Linux)

We had a Gentoo Linux server (that was updated weekly or bi weekly) that higher ups claimed did a denial of service attack on the whole local network and brought it down. Are there any log files we ...
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Repetitive / incessant hits to pages, blank referrer, non-malicious

I asked this question last week, and followed the debugging advice and now have additional information. I have an odd problem-- on a high traffic website (millions of visitors a month), every day we ...
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How to stop repetitive hits from same host to same URL?

I have an odd problem-- on a high traffic website (millions of visitors a month), every day we get about 20 or so situations where one host begins incessantly requesting the same page, over and over-- ...
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MSSQL 2005 on port 1433 gets DOS from infected servers

I have a SQL Server 2005 server hosted outside my firewall at a data center. It is fully up-to-date on patches, etc. There's some old MSSQL worm (Slammer?) that STILL infects thousands of servers ...
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(D)DOS - tcpdump established connections analysis (too many established connections)

¿How can I debug this problem? (I've got full tcpdump captures) I have a TCP server into which many clients establish persistent connections. Normally all these clients behave, and I never reach ...
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DDoS attacks [duplicate]

How to prevent DDoS attacks on Windows/IIS servers ?
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Do reports of packet flooding suggest a DOS attacK?

Our E1 connection is being closed by our firewall*. It happens intermittently every few days. I find log entries like this one around the same time as the dropout: Jun 2 09:53:35 sg580 kernel: ...
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Is account lockout a denial of service attack waiting to happen?

The default behaviour of windows is to lockout an account after a number of failed authentication attempts (usually three).. This means that with the following net use \\targetmachine\c$ ...
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What are the best techniques for preventing denial of service attacks?

Currently I have been using (D)DoS-Deflate to manage such situations on numerous remote servers, along with Apache JMeter for load testing. Overall it has been working fairly well, although I'd like ...