AlliedModders - Block ddos steam Fail2Ban

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Re: Block ddos steam Fail2Ban

I can't imagine this working. More professional DDoS attacks rely on sending the maximum amount of data on random UDP ports per packet. The idea is to overload the router with data. In this manner, there is no possible way to, with software, block a DDoS attack.

Mainly, underage script kiddies rely on ICMP packet flooding (Ping protocol) with a copious amount of ping.exe files running. The end result would the be the same (overloading the router) if the attacker's connection was strong enough to send that many packets. However, most likely it isn't, and results in lag instead of an actual denial of service.
Edit: More recently, kids have been buying $10 VPS accounts and using them to run packet flooding scripts.

In conclusion, your router would be overloaded before the packets had a chance to reach your server. Typically, this is what can bring down a network of datacenter servers that were attached to a single router. It is for this reason that DDoS attacks must be prevented at the hardware level, and this is actually done by some datacenters, which actually advertise their "DDoS protection." I have purchased one of those servers, and I have to say that it protected me from an attack that used hundreds of bots (each with at LEAST 10 mb/s)

Re: Block ddos steam Fail2Ban

You guys should first know the difference between DoS and DDoS Attacks.

DDoS != DoS.

And I think we are talking about DoS attacks here, which can be blocked by filters. DDoS can't be blocked by the system, if anything can block DDoS attacks then it would be load balancers...

Re: Block ddos steam Fail2Ban

Quote:

Originally Posted by berni (Post 1312364)

This is exactly what I was trying to point out. This man has the correct idea, guys. You should listen to him.

Re: Block ddos steam Fail2Ban

Steven, I'm pretty sure I know what it is. I've had it done to me before on my home connection.

>:/

I may not know everything about it, but I know the symptoms. So if this won't work for DDoS then I should look somewhere else.

Re: Block ddos steam Fail2Ban

Quote:

Originally Posted by loraliromance (Post 1315343)

Wow you should rely read the ONLY way to slow a true DDoS is have load balancing. But good thing most people who DDoS game servers are script kiddies and use SyN floods so you should just use iptables on the input chain to drop not reject all SyN/ICPM packets just google it also you can set iptables to stop people from flooding you udp ports. Between thoes two things you should slow down or even stop weak DDoS attacks. Do not think this is a 100% fix for DDoS attacks......

Re: Block ddos steam Fail2Ban

You should read, I never said I could stop it I just said i'd have to look somewhere else to try and fix the issue. It's a bit hard when the guy that did it to me keeps trying to find my new server. So i'm paranoid. Also, I know how the whole script things goes it's not like their aren't a gazillion people that are silly on hl1 mods spamming them to death :P

Re: Block ddos steam Fail2Ban

Group,

I'm trying to understand 1) how to implement this, 2) how this works.

In the IP Tables rules, the following is presented,

Code:

iptables -A INPUT -i eth0 -p udp --dport your_port -m length --length 28 -j REJECT_FLOOD28

Does the "your_port" part mean, the ports which my game servers are on? For example, 27015, 27016, etc?

Also, what part does the fail2ban program play in the equation?

Much thanks in advance!
Knight
Knight Vision Systems
http://www.knightvisionsystems.com

Re: Block ddos steam Fail2Ban

Quote:

Originally Posted by Knight Vision Systems (Post 1437423)

Group,

Code:

iptables -A INPUT -i eth0 -p udp --dport your_port -m length --length 28 -j REJECT_FLOOD28

Does the "your_port" part mean, the ports which my game servers are on? For example, 27015, 27016, etc?

Hi, sorry for late intervention, i just was googling, and arrived here...

Yes, here is to monitorize the port, but I have removed the port, to monitorize all, even, in my server I have just 5060, and 443 open... But I did:

Quote:

iptables -A INPUT -i eth0 -p udp -m length --length 28 -j

But I have a question:

In the jail conf, I'm missing the action, dose the action should be to deliver back to the iptables?? I have did:

Quote:

[ddos]
enabled = true
#port = 27015,27025,27050,28000,29000 ## I comminted out the port, to monitor all ports!
protocol = udp
filter = ddos
logpath = /var/log/messages
maxretry = 2
bantime = 60000
action = iptables[name=ddos-404-SLT] ## Dose this action here is correct??

Thank you in advance!

Re: Block ddos steam Fail2Ban

Quote:

Originally Posted by cmer (Post 961824)

opens the file /etc/fail2ban/jail.conf and we add

Quote:

Originally Posted by Fuck For Fun (Post 2658624)

What the fuck did I see here now?

Bad idea. Upgrades overwrite jail.conf.:rtfm:

Quote:

9 # HOW TO ACTIVATE JAILS:
10 #
11 # YOU SHOULD NOT MODIFY THIS FILE.
12 #
13 # It will probably be overwritten or improved in a distribution update.
14 #
15 # Provide customizations in a jail.local file or a jail.d/customisation.local.

According to this article https://gamebanana.com/threads/128192
cstrike-planet.com disappeared 11 years ago. [counter-strike] has been default in fail2ban years before this thread was written.

I see IP rules threads to offloading module threads while we have had one all along with fail2ban preconfigured. The logpath is out of date and needs to point to /var/log/messages in most instances.

Code:


/etc/fail2ban/jail.conf

[counter-strike]

logpath = /opt/cstrike/logs/L[0-9]*.log
# Firewall: <a href="http://www.cstrike-planet.com/faq/6" target="_blank" rel="nofollow noopener">http://www.cstrike-planet.com/faq/6</a>
tcpport = 27030,27031,27032,27033,27034,27035,27036,27037,27038,27039
udpport = 1200,27000,27001,27002,27003,27004,27005,27006,27007,27008,27009,27010,27011,27012,27013,27014,27015
action  = %(banaction)s[name=%(__name__)s-tcp, port="%(tcpport)s", protocol="tcp", chain="%(chain)s", actname=%(banaction)s-tcp]
           %(banaction)s[name=%(__name__)s-udp, port="%(udpport)s", protocol="udp", chain="%(chain)s", actname=%(banaction)s-udp]