Raised This Month: $12 Target: $400
 3% 

Help stopping DoS attack Ubuntu 16.04


Post New Thread Reply   
 
Thread Tools Display Modes
Author Message
Santi.
Member
Join Date: Oct 2010
Location: Cordoba(Argentina)
Old 09-10-2018 , 22:20   Help stopping DoS attack Ubuntu 16.04
Reply With Quote #1

Hi, Does anyone know how to stop DoS attacks? Have you any good tutorial?

We're having a lot of problems 'cause of brazilians :/
Santi. is offline
VPPGamingNetwork
Veteran Member
Join Date: Sep 2012
Location: Japan
Old 09-10-2018 , 22:23   Re: Help stopping DoS attack Ubuntu 16.04
Reply With Quote #2

get a host with good ddos protection, but that might be very expensive depending on your location
__________________

We provide MOTD Ads
Net 1 payments
Visit us
VPPGamingNetwork is offline
Santi.
Member
Join Date: Oct 2010
Location: Cordoba(Argentina)
Old 09-10-2018 , 22:25   Re: Help stopping DoS attack Ubuntu 16.04
Reply With Quote #3

Quote:
Originally Posted by VPPGamingNetwork View Post
get a host with good ddos protection, but that might be very expensive depending on your location
Right, but it's no DDoS, it's DoS, so I don't know very well how to use iptables to limit the connections from some potential attacker
Santi. is offline
PerfectLaugh
Junior Member
Join Date: Oct 2014
Old 09-10-2018 , 23:16   Re: Help stopping DoS attack Ubuntu 16.04
Reply With Quote #4

Did you have wireshark pcap file on that server?
PerfectLaugh is offline
lugui
Senior Member
Join Date: Feb 2016
Location: GetClientAbsOrigin();
Old 09-19-2018 , 08:42   Re: Help stopping DoS attack Ubuntu 16.04
Reply With Quote #5

sudo iptables -t nat -A INPUT -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -m connlimit --connlimit-above 15 --connlimit-mask 32 --connlimit-saddr -j DROP
sudo iptables -t nat -A INPUT -p udp -m connlimit --connlimit-above 15 --connlimit-mask 32 --connlimit-saddr -j DROP

Run this. It will drop any IP that makes more than 15 conections (you can lower it if you want)

Last edited by lugui; 09-19-2018 at 08:46.
lugui is offline
sphinx
Senior Member
Join Date: Jun 2005
Location: E.U. / localhost
Old 09-23-2018 , 03:10   Re: Help stopping DoS attack Ubuntu 16.04
Reply With Quote #6

Quote:
Originally Posted by lugui View Post
sudo iptables -t nat -A INPUT -p tcp -m tcp --tcp-flags FIN,SYN,RST,ACK SYN -m connlimit --connlimit-above 15 --connlimit-mask 32 --connlimit-saddr -j DROP
sudo iptables -t nat -A INPUT -p udp -m connlimit --connlimit-above 15 --connlimit-mask 32 --connlimit-saddr -j DROP

Run this. It will drop any IP that makes more than 15 conections (you can lower it if you want)
this works only if the flood comes from the same ip address (which is a very rare case), but not for ddos flood, which can be mitigated only upstream.

Last edited by sphinx; 09-24-2018 at 02:46.
sphinx is offline
e54385991
AlliedModders Donor
Join Date: Aug 2013
Old 09-23-2018 , 09:46   Re: Help stopping DoS attack Ubuntu 16.04
Reply With Quote #7

No way to defend udp spoofing (faked ip)
apart from white ip list

Last edited by e54385991; 09-23-2018 at 09:55.
e54385991 is offline
Send a message via ICQ to e54385991
TheHap
Member
Join Date: Feb 2018
Old 09-23-2018 , 12:43   Re: Help stopping DoS attack Ubuntu 16.04
Reply With Quote #8

hello,

send me log i help you.
TheHap is offline
Puppetmaster
Senior Member
Join Date: Jun 2015
Location: Probably at a computer.
Old 09-26-2018 , 18:07   Re: Help stopping DoS attack Ubuntu 16.04
Reply With Quote #9

Quote:
Originally Posted by e54385991 View Post
No way to defend udp spoofing (faked ip)
apart from white ip list
Unfortunately this is the answer.

There are definitely more robust systems out there in other games such as the one which ARK Survival uses where it uses a steam relay. The downside is that it adds additional latency.
__________________

GZS Servers
Puppetmaster is offline
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 06:40.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Theme made by Freecode