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Questions tagged [ddos]

A distributed denial of service attack (DDoS) occurs when multiple systems flood the bandwidth or resources of a targeted system, usually one or more web servers. These systems are compromised by attackers using a variety of methods.

A distributed denial of service attack (DDoS) occurs when multiple systems flood the bandwidth or resources of a targeted system, usually one or more web servers. These systems are compromised by attackers using a variety of methods.

For information on what to do about a DDoS attack that is underway, see How can I stop a currently active DDoS attack?

629 questions
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Tools for simulating DDoS attacks

I wanted to test my website if it can sustain strong DDoS's, but I don't know which tools could I use to simulate them in my website. What tools are used to simulate DDoS? I found bonesi but it was last updated 2 years ago.
Jürgen Paul
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Site has been under a massive DDOS attack for 5 weeks now

One of my sites has been getting attacked for over 5 weeks. Im currently employing serverorigin.com proxy services to fight it, since doing it on the server proved to be futile. They tell me that the attack spikes at 400k packets per second... and…
user11350
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3 answers

I know how to scale my software, but how to prevent downtime because of network outages?

We are running rather large LAMP sites which scale well software wise. We use redundant load balancers in front of a bunch of webservers using MySQL via a proxy in master-slave-slave-slave. We are using a very large US provider. They are not very…
CharlesS
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Will MX records with a longer TTL help mitigate effects of DoS attack?

We have our email hosted at Google Apps, and have our DNS servers for the domain setup at Namecheap. About a month ago our website went down (not a big deal, since it's most just a contact info page), but we were also unable to receive email for…
Peter
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How to prevent DDoS attacks?

I am a creator of a flash game server. I use cloudflare for my site, however the game tcp server cant be protected by CloudFlare. For about 2 months some person DDoSes my game using direct ip. Every VPS/Dedicated server provider instantly null…
user2196536
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Windows server 2008, a very small DDoS is able to kill my server

So I have this i7 3.2Ghz 6-core dedicated server running Windows Server 2008, with a 1Gbps internet speed. Everything runs fine and nice, and the machine is strong enough to handle even up to 700 Mbps DoS attacks very easy.. no lag, no…
Reacen
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My server is getting SYN Flooded, i have a few questions

my server is getting attacked, it seems to be a syn flood, and he is spoofing IP's. sudo netstat -anp |grep 'tcp\|udp' | awk '{print $5}' | cut -d: -f1 | sort | uniq -c | sort -n returns this. ... 4 94.144.63.102 5 91.100.45.134 6…
user3908531
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How to protect from DDOS attack that is coming from an exit node

Newroz Telecom (an ISP) is using an exit node (or gateway) for each city they operate in. That is all the users in city A is sharing one public IP (when the users go to a website to show their IP they all get the same result). I am having DDOS…
zertux
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How can I implement an ip whitelist to protect my server?

I'm going to start running a gameserver soon and I want a way to reduce the the damage of a denial of service attack. I want to make it so when someone joins the game their ip adress is added to a textfile (can already do this) and In the event of…
John Michael
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Redundant Router and Load Balancing vs. DDoS attack

With a small server farm at a hoster with great support and conditions, I worry about the increasing number of DDoS attacks against this hoster (not my web project, but other clients on the same location). I have booked a redundant router and load…
colgatta
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Best Practice for captcha based protection against D.O.S to Nginx Proxy

The idea is explained here In simple words, Nginx Proxy plays the role of load balance and transmits the HTTP/HTTPS requests to servers. If the number of request times within a certain period from an individual IP exceeds a threshold, it will…
Mr.Wang from Next Door
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Monitor DoS attack with snmp

Is there any way to monitor DoS attacks with SNMP or any other software which based on Linux and could monitor router / switches and alert when a DoS attack is observed?
User4283
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ddos protection for dedicated server

Whats the best way to protect a linux root server from a ddos attack? I just want to inform myself about the issue. I'm wondering I haven't found a good solution. anybody has one? thanks!
dudewithcar
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0 answers

How does DDOS mitigation partners filter out the bad traffic?

I am currently reading about ddos mitigation techniques. I came across a thing called proxy servers and ddos mitigation partners, who can help prevent ddos. The proxy servers actually hide your actual server's ip, and these are ddos protected with…
Ayush Goyal
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Is it DDOS attack?

For three successive days, now, I'm having four or five unique servers' queries being denied by my csf firewall, which are renamed in the following extract I got from my log as "www.example1.com", "www.example2.com", "ns1.example3.com",…
ajax20
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