Linked Questions

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2answers
9k views

How do you prevent UDP-flood based DDOS attacks on a DNS server? [duplicate]

I'm studying networking at the moment, and it just occurred to me that one can easily forge DNS requests with fake IP addresses (since they use UDP). Since DNS relies on UDP for communication, ...
2
votes
3answers
5k views

Identifying DDOS Attacks on Windows 2008 Servers [duplicate]

I recently was notified by my monitoring service that a few Windows 2008 servers (hyper-v instances) were down. I logged into the Hyper-V box and noticed everything was super slow. I opened task ...
0
votes
1answer
4k views

DDOS Attack detection with netstat [duplicate]

I have a server, today load of my server over 20, i was found a command that detect alive connection to server for DDOS detection and reject IP. netstat -anp | grep 'tcp\|udp' | awk '{print $5}' | ...
2
votes
6answers
573 views

Securing against DDoS [duplicate]

My client would like to have his eCommerce (custom-made) site secured from DDoS attacks. What strategies can I implement? There are multiple forms in the purchasing flow --- searching, drilling-down ...
3
votes
2answers
1k views

Can DDoS be stopped with BGP? [duplicate]

When I am experiencing DDoS @10Gbps, if I have BGP router with 10M table entries in it, can I perform search on the offensive network? I would do this the way, that first I would remove routing to me ...
6
votes
5answers
2k views

DDoS Protection Services - are they good enough? [duplicate]

first of all, I understand that it's better to have DDoS protections on data center level. But our DC is not ready to provide good quality of protection. So we thinking about using some external DDoS ...
3
votes
2answers
2k views

Allowing apache to write with iptables [duplicate]

Since to days ago I'm receiving DDOS atacks in my server. I've installed mod_evasive in apache and it works right! It writes the log and send the email with de IPs. But there's a problem: Apache ...
1
vote
1answer
10k views

Snort rules for syn flood / ddos? [duplicate]

Can someone provide me rules to detect following attack : hping3 -S -p 80 --flood --rand-source [target] I'm having problem with rules since packet comes from random source. My current rules is : ...
4
votes
3answers
884 views

In Linux, does using route to blackhole an IP result in better performance than dropping in iptables? [duplicate]

During a DDOS attack, if we are finding IPs we want to block will we see better performance using a null route as opposed to iptables? Null routing we would do something like: ip route add blackhole ...
3
votes
3answers
675 views

Can't stop DDOS [duplicate]

I need a little help dealing with ddos. I'm experiencing 1gb ddos attack on my server and I don't know how to stop it. (1gbs is the maximum speed of the server.) I've the following iptables rules: ...
2
votes
4answers
2k views

Mitigating an http flood? [duplicate]

I have a ddos protection proxy in place to deal with SYN floods and such. But http floods are still getting through. For some reason their ddos proxy is not blocking any of the flood. So there are ...
2
votes
5answers
625 views

DDoS attacks [duplicate]

How to prevent DDoS attacks on Windows/IIS servers ?
2
votes
4answers
366 views

Apache getting DDoS [duplicate]

My apache server is currently getting DDoSed. It looks like all the traffic is referrals from the file server of a russian file sharing site. How can I block only the traffic which is coming from the ...
1
vote
2answers
2k views

Varnish and Connection Flood (DoS - DDoS) [duplicate]

I've been playing around with the Varnish cache server and I got my webpage up lightning fast, it gets 97 Points in Google's Pagespeed and 100 @ Pingdom's. I used Varnish (proxies to nginx), NGINX ...
1
vote
5answers
709 views

Identifying DOS attack [duplicate]

I'm suspecting that one of my servers is attacked some time ago. My question is how can I identify a DOS or DDOS attack while under attack or after the attack has finished?

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