How to stop syn flood attack?
- Thread starter Zeoxy
- Start date
nes22
Junior Member
- Feb 23, 2016
- 101
- 18
Number one is to ban all the ips attacking. Most attacks only work if it ends up using your VPS cpu/bandwidth to send a response back. Very rarely is an attack strong enough to put you down by just sending packets alone. Caching can also help with the CPU load for ips you don't ban.
If there's thousands of ips then the best thing to do would be to program an autoban feature. If an IP attempts to connect 10-50 times then automatically place it on a list to be banned. If you have Wordpress you can get plugins that do this so it saves time.
If there's thousands of ips then the best thing to do would be to program an autoban feature. If an IP attempts to connect 10-50 times then automatically place it on a list to be banned. If you have Wordpress you can get plugins that do this so it saves time.
tasburrfoot
Regular Member
- Dec 16, 2008
- 338
- 162
https://www.google.ca/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=how to stop syn flood
Usually now a days with most Datacenters connections/protections it's pretty damn hard to knock a site offline without a massive and dedicated botnet, and pointing that at a guy getting "100 views a day from instagram" would be a gross waste of resources.
Basically you need to decrease your timeout time's for SYN packets(syn packets wont hang for as long), increase your SYN-Received backlog, and you may need to use SYN cookies as well.
Noah Hawryshko
Senior Member
- Apr 28, 2016
- 901
- 890
HAH! I've got to put that in my back pocket for later. Great post.
OP, you've got to shut off SYN. Just completely shut it off. Take away everything SYN and then let your server operate normally. Then it won't matter if you get flooded with SYN because your server will just ignore everything SYN. It's perfect!
Who needs SYN anyway? It probably doesn't even do anything important...
tasburrfoot
Regular Member
- Dec 16, 2008
- 338
- 162
I'd be careful pointing anything at anything related to the Alphabet Soup. Chances are they won't like that very much, and apparently it's pretty easy to be considered a terrorist these days(especially for foreign nationals).
Noah Hawryshko
Senior Member
- Apr 28, 2016
- 901
- 890
Well I'll point them to the European alphabet soup then. I'll also send them this meme:
