1
vote
3answers
382 views

High CPU usage in random IP/Port UDP DDoS

I have been getting these UDP floods with random IPs and ports. randomip:randomport -> myip:randomport 0 byte payload For some reason it is using a lot of CPU. Here is the results of perf top -e ...
-1
votes
2answers
427 views

Can't resolve issue: iptables: No chain/target/match by that name

So I am trying to setup shorewall firewall on my linux vps. The vps is running ubuntu 12.10. When I type $ shorewall check I get this error. iptables: No chain/target/match by that name. ERROR: ...
0
votes
4answers
994 views

How to tune Linux kernel to withstand DDoS? (HAProxy)

Please do not reply with "this is not possible", as it's waste of time. I am developing cloud appliance and I have a valid reason to protect this layer against DDoS, and there are few companies doing ...
1
vote
1answer
271 views

How to block everything with IPTABLES?

I would like to block everything EXCEPT SSH/FTP/HTTP/POSTFIX and MySQL. With "everything" I mean all the other ports, block pings etc etc.
0
votes
1answer
42 views

enabling ipv4 forwarding locked up machine. ideas?

Hey. I'm running cent 5.5 64-bit, 1 nic, eth0. I enabled ipv4 forwarding via: echo '1' > /proc/sys/net/ipv4/ip_forward and the machine locks up. cant switch ttys cant ssh into it. Had to hard ...